Rules In DISA STIG for AlmaLinux 8


Total Missing Implemented Coverage STIG ids missing rule
379 39 340 89.71% RHEL-08-010090 RHEL-08-010100 RHEL-08-010159 RHEL-08-010163 RHEL-08-010180 RHEL-08-010287 RHEL-08-010400 RHEL-08-010560 RHEL-08-010572 RHEL-08-010710 RHEL-08-010731 RHEL-08-010741 RHEL-08-020011 RHEL-08-020013 RHEL-08-020015 RHEL-08-020016 RHEL-08-020017 RHEL-08-020018 RHEL-08-020019 RHEL-08-020020 RHEL-08-020021 RHEL-08-020023 RHEL-08-020025 RHEL-08-020026 RHEL-08-020031 RHEL-08-020032 RHEL-08-020080 RHEL-08-020081 RHEL-08-020082 RHEL-08-020332 RHEL-08-030181 RHEL-08-030590 RHEL-08-030620 RHEL-08-030630 RHEL-08-030640 RHEL-08-040020 RHEL-08-040090 RHEL-08-040137 RHEL-08-040150
V-ID CCI CAT Title Description Check Procedures Fixtext Version Mapped Rule
V-230221 366 high RHEL 8 must be a vendor-supported release. An operating system is considered "supported" if the vendor continues to provide security patches for the product. With an unsupported release, it will not be possible to resolve any security issue discovered in the system software. To verify that the installed operating system is supported, run the following command: $ grep -i "almalinux" /etc/almalinux-release The output should contain something similar to: AlmaLinux 8 Is it the case that the installed operating system is not supported? The installed operating system must be maintained by a vendor. AlmaLinux is supported by AlmaLinux. As the AlmaLinux vendor, AlmaLinux is responsible for providing security patches. RHEL-08-010000 installed_OS_is_vendor_supported
V-245540 1233 medium The RHEL 8 operating system must implement the Endpoint Security for Linux Threat Prevention tool. Virus scanning software can be used to detect if a system has been compromised by computer viruses, as well as to limit their spread to other systems. To verify that McAfee Endpoint Security for Linux is running, run the following command: $ sudo ps -ef | grep -i mfetpd Is it the case that virus scanning software is not running? Install McAfee Endpoint Security for Linux antivirus software which is provided for DoD systems and uses signatures to search for the presence of viruses on the filesystem. RHEL-08-010001 agent_mfetpd_running
V-230222 366 medium RHEL 8 vendor packaged system security patches and updates must be installed and up to date. Installing software updates is a fundamental mitigation against the exploitation of publicly-known vulnerabilities. If the most recent security patches and updates are not installed, unauthorized users may take advantage of weaknesses in the unpatched software. The lack of prompt attention to patching could result in a system compromise. Run the following command to install updates:
$ sudo yum update
If the system is not configured to use repos, updates (in the form of RPM packages) can be manually downloaded from the repos and installed using rpm.

NOTE: U.S. Defense systems are required to be patched within 30 days or sooner as local policy dictates.
RHEL-08-010010 security_patches_up_to_date
V-230223 68 high RHEL 8 must implement NIST FIPS-validated cryptography for the following: to provision digital signatures, to generate cryptographic hashes, and to protect data requiring data-at-rest protections in accordance with applicable federal laws, Executive Orders, directives, policies, regulations, and standards. Use of weak or untested encryption algorithms undermines the purposes of utilizing encryption to protect data. The operating system must implement cryptographic modules adhering to the higher standards approved by the federal government since this provides assurance they have been tested and validated. To verify that kernel parameter 'crypto.fips_enabled' is set properly, run the following command: sysctl crypto.fips_enabled The output should contain the following: crypto.fips_enabled = 1 Is it the case that crypto.fips_enabled is not 1? System running in FIPS mode is indicated by kernel parameter 'crypto.fips_enabled'. This parameter should be set to 1 in FIPS mode. To enable FIPS mode, run the following command:
fips-mode-setup --enable
RHEL-08-010020 sysctl_crypto_fips_enabled
V-230224 1199 medium All RHEL 8 local disk partitions must implement cryptographic mechanisms to prevent unauthorized disclosure or modification of all information that requires at rest protection. The risk of a system's physical compromise, particularly mobile systems such as laptops, places its data at risk of compromise. Encrypting this data mitigates the risk of its loss if the system is lost. Check the system partitions to determine if they are encrypted with the following command: blkid Output will be similar to: /dev/sda1: UUID=" ab12c3de-4f56-789a-8f33-3850cc8ce3a2 " TYPE="crypto_LUKS" /dev/sda2: UUID=" bc98d7ef-6g54-321h-1d24-9870de2ge1a2 " TYPE="crypto_LUKS" Pseudo-file systems, such as /proc, /sys, and tmpfs, are not required to use disk encryption and are not a finding. Is it the case that partitions do not have a type of crypto_LUKS? AlmaLinux 8 natively supports partition encryption through the Linux Unified Key Setup-on-disk-format (LUKS) technology. The easiest way to encrypt a partition is during installation time.

For manual installations, select the Encrypt checkbox during partition creation to encrypt the partition. When this option is selected the system will prompt for a passphrase to use in decrypting the partition. The passphrase will subsequently need to be entered manually every time the system boots.

For automated/unattended installations, it is possible to use Kickstart by adding the --encrypted and --passphrase= options to the definition of each partition to be encrypted. For example, the following line would encrypt the root partition:
part / --fstype=ext4 --size=100 --onpart=hda1 --encrypted --passphrase=PASSPHRASE
Any PASSPHRASE is stored in the Kickstart in plaintext, and the Kickstart must then be protected accordingly. Omitting the --passphrase= option from the partition definition will cause the installer to pause and interactively ask for the passphrase during installation.

By default, the Anaconda installer uses aes-xts-plain64 cipher with a minimum 512 bit key size which should be compatible with FIPS enabled.

Detailed information on encrypting partitions using LUKS or LUKS ciphers can be found on the AlmaLinux 8 Documentation web site:
https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html/security_hardening/encrypting-block-devices-using-luks_security-hardening.
RHEL-08-010030 encrypt_partitions
V-230225 48 medium RHEL 8 must display the Standard Mandatory DoD Notice and Consent Banner before granting local or remote access to the system via a ssh logon. The warning message reinforces policy awareness during the logon process and facilitates possible legal action against attackers. Alternatively, systems whose ownership should not be obvious should ensure usage of a banner that does not provide easy attribution. To determine how the SSH daemon's Banner option is set, run the following command: $ sudo grep -i Banner /etc/ssh/sshd_config If a line indicating /etc/issue is returned, then the required value is set. Is it the case that the required value is not set? To enable the warning banner and ensure it is consistent across the system, add or correct the following line in /etc/ssh/sshd_config:
Banner /etc/issue
Another section contains information on how to create an appropriate system-wide warning banner.
RHEL-08-010040 sshd_enable_warning_banner
V-244519 48 medium RHEL 8 must display a banner before granting local or remote access to the system via a graphical user logon. Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.

For U.S. Government systems, system use notifications are required only for access via login interfaces with human users and are not required when such human interfaces do not exist.
To ensure a login warning banner is enabled, run the following: $ grep banner-message-enable /etc/dconf/db/gdm.d/* If properly configured, the output should be true. To ensure a login warning banner is locked and cannot be changed by a user, run the following: $ grep banner-message-enable /etc/dconf/db/gdm.d/locks/* If properly configured, the output should be /org/gnome/login-screen/banner-message-enable. Is it the case that it is not? In the default graphical environment, displaying a login warning banner in the GNOME Display Manager's login screen can be enabled on the login screen by setting banner-message-enable to true.

To enable, add or edit banner-message-enable to /etc/dconf/db/gdm.d/00-security-settings. For example:
[org/gnome/login-screen]
banner-message-enable=true
Once the setting has been added, add a lock to /etc/dconf/db/gdm.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/login-screen/banner-message-enable
After the settings have been set, run dconf update. The banner text must also be set.
RHEL-08-010049 dconf_gnome_banner_enabled
V-230226 48 medium RHEL 8 must display the Standard Mandatory DoD Notice and Consent Banner before granting local or remote access to the system via a graphical user logon. An appropriate warning message reinforces policy awareness during the logon process and facilitates possible legal action against attackers. To ensure the login warning banner text is properly set, run the following: $ grep banner-message-text /etc/dconf/db/gdm.d/* If properly configured, the proper banner text will appear. To ensure the login warning banner text is locked and cannot be changed by a user, run the following: $ grep banner-message-text /etc/dconf/db/gdm.d/locks/* If properly configured, the output should be /org/gnome/login-screen/banner-message-text. Is it the case that it does not? In the default graphical environment, configuring the login warning banner text in the GNOME Display Manager's login screen can be configured on the login screen by setting banner-message-text to 'APPROVED_BANNER' where APPROVED_BANNER is the approved banner for your environment.

To enable, add or edit banner-message-text to /etc/dconf/db/gdm.d/00-security-settings. For example:
[org/gnome/login-screen]
banner-message-text='APPROVED_BANNER'
Once the setting has been added, add a lock to /etc/dconf/db/gdm.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/login-screen/banner-message-text
After the settings have been set, run dconf update. When entering a warning banner that spans several lines, remember to begin and end the string with ' and use \n for new lines.
RHEL-08-010050 dconf_gnome_login_banner_text
V-230227 48 medium RHEL 8 must display the Standard Mandatory DoD Notice and Consent Banner before granting local or remote access to the system via a command line user logon. Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance.

System use notifications are required only for access via login interfaces with human users and are not required when such human interfaces do not exist.
To check if the system login banner is compliant, run the following command: $ cat /etc/issue Is it the case that it does not display the required banner? To configure the system login banner edit /etc/issue. Replace the default text with a message compliant with the local site policy or a legal disclaimer. The DoD required text is either:

You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions:
-The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations.
-At any time, the USG may inspect and seize data stored on this IS.
-Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose.
-This IS includes security measures (e.g., authentication and access controls) to protect USG interests -- not for your personal benefit or privacy.
-Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details.


OR:

I've read & consent to terms in IS user agreem't.
RHEL-08-010060 banner_etc_issue
V-230228 67 medium All RHEL 8 remote access methods must be monitored. Logging remote access methods can be used to trace the decrease the risks associated with remote user access management. It can also be used to spot cyber attacks and ensure ongoing compliance with organizational policies surrounding the use of remote access methods. To verify that remote access methods are logging to rsyslog, run the following command: grep -rE '(auth.\*|authpriv.\*|daemon.\*)' /etc/rsyslog.* The output should contain auth.*, authpriv.*, and daemon.* pointing to a log file. Is it the case that remote access methods are not logging to rsyslog? Logging of remote access methods must be implemented to help identify cyber attacks and ensure ongoing compliance with remote access policies are being audited and upheld. An examples of a remote access method is the use of the Remote Desktop Protocol (RDP) from an external, non-organization controlled network. The /etc/rsyslog.conf or /etc/rsyslog.d/*.conf file should contain a match for the following selectors: auth.*, authpriv.*, and daemon.*. If not, use the following as an example configuration:
auth.*;authpriv.*;daemon.*                              /var/log/secure
RHEL-08-010070 rsyslog_remote_access_monitoring
V-230229 medium RHEL 8, for PKI-based authentication, must validate certificates by constructing a certification path (which includes status information) to an accepted trust anchor. RHEL-08-010090 Missing Rule
V-230230 medium RHEL 8, for certificate-based authentication, must enforce authorized access to the corresponding private key. RHEL-08-010100 Missing Rule
V-230231 196 medium RHEL 8 must encrypt all stored passwords with a FIPS 140-2 approved cryptographic hashing algorithm. Passwords need to be protected at all times, and encryption is the standard method for protecting passwords. If passwords are not encrypted, they can be plainly read (i.e., clear text) and easily compromised. Passwords that are encrypted with a weak algorithm are no more protected than if they are kept in plain text.

Using a stronger hashing algorithm makes password cracking attacks more difficult.
Inspect /etc/login.defs and ensure the following line appears: ENCRYPT_METHOD SHA512 Is it the case that it does not? In /etc/login.defs, add or correct the following line to ensure the system will use SHA-512 as the hashing algorithm:
ENCRYPT_METHOD SHA512
RHEL-08-010110 set_password_hashing_algorithm_logindefs
V-230232 196 medium RHEL 8 must employ FIPS 140-2 approved cryptographic hashing algorithms for all stored passwords. The system must use a strong hashing algorithm to store the password. The system must use a sufficient number of hashing rounds to ensure the required level of entropy. Check that the interactive user account passwords are using a strong password hash with the following command: # sudo cut -d: -f2 /etc/shadow $6$kcOnRq/5$NUEYPuyL.wghQwWssXRcLRFiiru7f5JPV6GaJhNC2aK5F3PZpE/BCCtwrxRc/AInKMNX3CdMw11m9STiql12f/ Password hashes ! or * indicate inactive accounts not available for logon and are not evaluated. If any interactive user password hash does not begin with $6, this is a finding. Is it the case that passwords hashed with an unauthorized algorithm are found in /etc/shadow? Verify the operating system requires the shadow password suite configuration be set to encrypt interactive user passwords using a strong cryptographic hash. Check that the interactive user account passwords are using a strong password hash with the following command:
# sudo cut -d: -f2 /etc/shadow
$6$kcOnRq/5$NUEYPuyL.wghQwWssXRcLRFiiru7f5JPV6GaJhNC2aK5F3PZpE/BCCtwrxRc/AInKMNX3CdMw11m9STiql12f/
Password hashes ! or * indicate inactive accounts not available for logon and are not evaluated. If any interactive user password hash does not begin with $6, this is a finding.
RHEL-08-010120 accounts_password_all_shadowed_sha512
V-230233 196 medium The RHEL 8 password-auth file must be configured to use a sufficient number of hashing rounds. Using a higher number of rounds makes password cracking attacks more difficult. To verify the number of rounds for the password hashing algorithm is compliant, run the following command: $ grep rounds /etc/pam.d/password-auth The output should show the following match: rounds= Is it the case that it does not set the appropriate number of hashing rounds? Configure the number or rounds for the password hashing algorithm. This can be accomplished by using the rounds option for the pam_unix PAM module.

In file /etc/pam.d/password-auth append rounds= to the pam_unix.so file, as shown below:
password sufficient pam_unix.so ...existing_options... rounds=
The system's default number of rounds is 5000.
RHEL-08-010130 accounts_password_pam_unix_rounds_password_auth
V-244520 196 medium The RHEL 8 system-auth file must be configured to use a sufficient number of hashing rounds. Using a higher number of rounds makes password cracking attacks more difficult. To verify the number of rounds for the password hashing algorithm is compliant, run the following command: $ grep rounds /etc/pam.d/system-auth The output should show the following match: rounds= Is it the case that it does not set the appropriate number of hashing rounds? Configure the number or rounds for the password hashing algorithm. This can be accomplished by using the rounds option for the pam_unix PAM module.

In file /etc/pam.d/system-auth append rounds= to the pam_unix.so file, as shown below:
password sufficient pam_unix.so ...existing_options... rounds=
The system's default number of rounds is 5000.
RHEL-08-010131 accounts_password_pam_unix_rounds_system_auth
V-230234 213 high RHEL 8 operating systems booted with United Extensible Firmware Interface (UEFI) must require authentication upon booting into single-user mode and maintenance. Password protection on the boot loader configuration ensures users with physical access cannot trivially alter important bootloader settings. These include which kernel to use, and whether to enter single-user mode. To verify the boot loader superuser password has been set, run the following command: sudo grep "password" /etc/grub2-efi.cfg The output should show the following: password_pbkdf2 superusers-account ${GRUB2_PASSWORD} To verify the boot loader superuser account password has been set, and the password encrypted, run the following command: sudo cat /boot/efi/EFI/almalinux/user.cfg The output should be similar to: GRUB2_PASSWORD=grub.pbkdf2.sha512.10000.C4E08AC72FBFF7E837FD267BFAD7AEB3D42DDC 2C99F2A94DD5E2E75C2DC331B719FE55D9411745F82D1B6CFD9E927D61925F9BBDD1CFAA0080E0 916F7AB46E0D.1302284FCCC52CD73BA3671C6C12C26FF50BA873293B24EE2A96EE3B57963E6D7 0C83964B473EC8F93B07FE749AA6710269E904A9B08A6BBACB00A2D242AD828 Is it the case that it does not? The grub2 boot loader should have a superuser account and password protection enabled to protect boot-time settings.

Since plaintext passwords are a security risk, generate a hash for the password by running the following command:
$ grub2-setpassword
When prompted, enter the password that was selected.

Once the superuser password has been added, update the grub.cfg file by running:
grub2-mkconfig -o /boot/efi/EFI/almalinux/grub.cfg
RHEL-08-010140 grub2_uefi_password
V-244521 213 medium RHEL 8 operating systems booted with United Extensible Firmware Interface (UEFI) must require a unique superusers name upon booting into single-user mode and maintenance. Having a non-default grub superuser username makes password-guessing attacks less effective. To verify the boot loader superuser account has been set, run the following command: sudo grep -A1 "superusers" /etc/grub2-efi.cfg The output should show the following: set superusers="superusers-account" export superusers where superusers-account is the actual account name different from common names like root, admin, or administrator. Is it the case that it does not? The grub2 boot loader should have a superuser account and password protection enabled to protect boot-time settings.

To maximize the protection, select a password-protected superuser account with unique name, and modify the /etc/grub.d/01_users configuration file to reflect the account name change.

It is highly suggested not to use common administrator account names like root, admin, or administrator for the grub2 superuser account.

Change the superuser to a different username (The default is 'root').
$ sed -i 's/\(set superuser=\).*/\1"<unique user ID>"/g' /etc/grub.d/01_users


Once the superuser account has been added, update the grub.cfg file by running:
grub2-mkconfig -o /boot/efi/EFI/almalinux/grub.cfg
RHEL-08-010141 grub2_uefi_admin_username
V-244522 213 medium RHEL 8 operating systems booted with a BIOS must require a unique superusers name upon booting into single-user and maintenance modes. Having a non-default grub superuser username makes password-guessing attacks less effective. To verify the boot loader superuser account has been set, run the following command: sudo grep -A1 "superusers" /etc/grub2.cfg The output should show the following: set superusers="superusers-account" export superusers where superusers-account is the actual account name different from common names like root, admin, or administrator. Is it the case that it does not? The grub2 boot loader should have a superuser account and password protection enabled to protect boot-time settings.

To maximize the protection, select a password-protected superuser account with unique name, and modify the /etc/grub.d/01_users configuration file to reflect the account name change.

Do not to use common administrator account names like root, admin, or administrator for the grub2 superuser account.

Change the superuser to a different username (The default is 'root').
$ sed -i 's/\(set superuser=\).*/\1"<unique user ID>"/g' /etc/grub.d/01_users


Once the superuser account has been added, update the grub.cfg file by running:
grub2-mkconfig -o /boot/grub2/grub.cfg
RHEL-08-010149 grub2_admin_username
V-230235 213 high RHEL 8 operating systems booted with a BIOS must require authentication upon booting into single-user and maintenance modes. Password protection on the boot loader configuration ensures users with physical access cannot trivially alter important bootloader settings. These include which kernel to use, and whether to enter single-user mode. To verify the boot loader superuser password has been set, run the following command: sudo grep "superusers" /etc/grub2.cfg The output should show the following: password_pbkdf2 superusers-account ${GRUB2_PASSWORD} To verify the boot loader superuser account password has been set, and the password encrypted, run the following command: sudo cat /boot/grub2/user.cfg The output should be similar to: GRUB2_PASSWORD=grub.pbkdf2.sha512.10000.C4E08AC72FBFF7E837FD267BFAD7AEB3D42DDC 2C99F2A94DD5E2E75C2DC331B719FE55D9411745F82D1B6CFD9E927D61925F9BBDD1CFAA0080E0 916F7AB46E0D.1302284FCCC52CD73BA3671C6C12C26FF50BA873293B24EE2A96EE3B57963E6D7 0C83964B473EC8F93B07FE749AA6710269E904A9B08A6BBACB00A2D242AD828 Is it the case that it does not? The grub2 boot loader should have a superuser account and password protection enabled to protect boot-time settings.

Since plaintext passwords are a security risk, generate a hash for the password by running the following command:
$ grub2-setpassword
When prompted, enter the password that was selected.



Once the superuser password has been added, update the grub.cfg file by running:
grub2-mkconfig -o /boot/grub2/grub.cfg
RHEL-08-010150 grub2_password
V-230236 213 medium RHEL 8 operating systems must require authentication upon booting into rescue mode. This prevents attackers with physical access from trivially bypassing security on the machine and gaining root access. Such accesses are further prevented by configuring the bootloader password. To check if authentication is required for single-user mode, run the following command: $ grep sulogin /usr/lib/systemd/system/rescue.service The output should be similar to the following, and the line must begin with ExecStart and /usr/lib/systemd/systemd-sulogin-shell. ExecStart=-/usr/lib/systemd/systemd-sulogin-shell rescue Is it the case that the output is different? Single-user mode is intended as a system recovery method, providing a single user root access to the system by providing a boot option at startup. By default, no authentication is performed if single-user mode is selected.

By default, single-user mode is protected by requiring a password and is set in /usr/lib/systemd/system/rescue.service.
RHEL-08-010151 require_singleuser_auth
V-244523 213 medium RHEL 8 operating systems must require authentication upon booting into emergency mode. This prevents attackers with physical access from trivially bypassing security on the machine and gaining root access. Such accesses are further prevented by configuring the bootloader password. To check if authentication is required for emergency mode, run the following command: $ grep sulogin /usr/lib/systemd/system/emergency.service The output should be similar to the following, and the line must begin with ExecStart and /usr/lib/systemd/systemd-sulogin-shell. ExecStart=-/usr/lib/systemd/systemd-sulogin-shell emergency Is it the case that the output is different? Emergency mode is intended as a system recovery method, providing a single user root access to the system during a failed boot sequence.

By default, Emergency mode is protected by requiring a password and is set in /usr/lib/systemd/system/emergency.service.
RHEL-08-010152 require_emergency_target_auth
V-244524 medium The RHEL 8 pam_unix.so module must be configured in the system-auth file to use a FIPS 140-2 approved cryptographic hashing algorithm for system authentication. RHEL-08-010159 Missing Rule
V-230237 803 medium The RHEL 8 pam_unix.so module must be configured in the password-auth file to use a FIPS 140-2 approved cryptographic hashing algorithm for system authentication. Passwords need to be protected at all times, and encryption is the standard method for protecting passwords. If passwords are not encrypted, they can be plainly read (i.e., clear text) and easily compromised. Passwords that are encrypted with a weak algorithm are no more protected than if they are kepy in plain text.

This setting ensures user and group account administration utilities are configured to store only encrypted representations of passwords. Additionally, the crypt_style configuration option ensures the use of a strong hashing algorithm that makes password cracking attacks more difficult.
Inspect the password section of /etc/pam.d/system-auth and ensure that the pam_unix.so module includes the argument sha512: $ grep sha512 /etc/pam.d/system-auth Is it the case that it does not? The PAM system service can be configured to only store encrypted representations of passwords. In /etc/pam.d/system-auth, the password section of the file controls which PAM modules execute during a password change. Set the pam_unix.so module in the password section to include the argument sha512, as shown below:
password    sufficient    pam_unix.so sha512 other arguments...

This will help ensure when local users change their passwords, hashes for the new passwords will be generated using the SHA-512 algorithm. This is the default.
RHEL-08-010160 set_password_hashing_algorithm_systemauth
V-230238 803 medium RHEL 8 must prevent system daemons from using Kerberos for authentication. The key derivation function (KDF) in Kerberos is not FIPS compatible. Run the following command to see if there are some keytabs that would potentially allow the use of Kerberos by system daemons. $ ls -la /etc/*.keytab The expected result is ls: cannot access '/etc/*.keytab': No such file or directory Is it the case that it is present on the system? Kerberos is not an approved key distribution method for Common Criteria. To prevent using Kerberos by system daemons, remove the Kerberos keytab files, especially /etc/krb5.keytab. RHEL-08-010161 kerberos_disable_no_keytab
V-230239 803 medium The krb5-workstation package must not be installed on RHEL 8. Kerberos is a network authentication system. The krb5-workstation package contains the basic Kerberos programs (kinit, klist, kdestroy, kpasswd). Currently, Kerberos does not utilize FIPS 140-2 cryptography and is not permitted on Government networks, nor is it permitted in many regulatory environments such as HIPAA. Run the following command to determine if the krb5-workstation package is installed: $ rpm -q krb5-workstation Is it the case that the package is installed? The krb5-workstation package can be removed with the following command:
$ sudo yum erase krb5-workstation
RHEL-08-010162 package_krb5-workstation_removed
V-237640 medium The krb5-server package must not be installed on RHEL 8. RHEL-08-010163 Missing Rule
V-230240 1084 medium RHEL 8 must use a Linux Security Module configured to enforce limits on system services. Setting the SELinux state to enforcing ensures SELinux is able to confine potentially compromised processes to the security policy, which is designed to prevent them from causing damage to the system or further elevating their privileges. Check the file /etc/selinux/config and ensure the following line appears: SELINUX= Is it the case that SELINUX is not set to enforcing? The SELinux state should be set to at system boot time. In the file /etc/selinux/config, add or correct the following line to configure the system to boot into enforcing mode:
SELINUX=
RHEL-08-010170 selinux_state
V-230241 1084 low RHEL 8 must have policycoreutils package installed. Security-enhanced Linux is a feature of the Linux kernel and a number of utilities with enhanced security functionality designed to add mandatory access controls to Linux. The Security-enhanced Linux kernel contains new architectural components originally developed to improve security of the Flask operating system. These architectural components provide general support for the enforcement of many kinds of mandatory access control policies, including those based on the concepts of Type Enforcement, Role-based Access Control, and Multi-level Security. policycoreutils contains the policy core utilities that are required for basic operation of an SELinux-enabled system. These utilities include load_policy to load SELinux policies, setfiles to label filesystems, newrole to switch roles, and so on. Run the following command to determine if the policycoreutils package is installed: $ rpm -q policycoreutils Is it the case that the package is not installed? The policycoreutils package can be installed with the following command:
$ sudo yum install policycoreutils
RHEL-08-010171 package_policycoreutils_installed
V-230242 medium All RHEL 8 public directories must be owned by root or a system account to prevent unauthorized and unintended information transferred via shared system resources. RHEL-08-010180 Missing Rule
V-230243 1090 medium A sticky bit must be set on all RHEL 8 public directories to prevent unauthorized and unintended information transferred via shared system resources. Failing to set the sticky bit on public directories allows unauthorized users to delete files in the directory structure.

The only authorized public directories are those temporary directories supplied with the system, or those designed to be temporary file repositories. The setting is normally reserved for directories used by the system, by users for temporary file storage (such as /tmp), and for directories requiring global read/write access.
To find world-writable directories that lack the sticky bit, run the following command: $ sudo find / -xdev -type d -perm 002 ! -perm 1000 Is it the case that any world-writable directories are missing the sticky bit? When the so-called 'sticky bit' is set on a directory, only the owner of a given file may remove that file from the directory. Without the sticky bit, any user with write access to a directory may remove any file in the directory. Setting the sticky bit prevents users from removing each other's files. In cases where there is no reason for a directory to be world-writable, a better solution is to remove that permission rather than to set the sticky bit. However, if a directory is used by a particular application, consult that application's documentation instead of blindly changing modes.
To set the sticky bit on a world-writable directory DIR, run the following command:
$ sudo chmod +t DIR
RHEL-08-010190 dir_perms_world_writable_sticky_bits
V-230244 1133 medium RHEL 8 must be configured so that all network connections associated with SSH traffic are terminated at the end of the session or after 10 minutes of inactivity, except to fulfill documented and validated mission requirements. This ensures a user login will be terminated as soon as the ClientAliveInterval is reached. To ensure ClientAliveInterval is set correctly, run the following command: $ sudo grep ClientAliveCountMax /etc/ssh/sshd_config If properly configured, the output should be: ClientAliveCountMax 0 In this case, the SSH idle timeout occurs precisely when the ClientAliveInterval is set. Is it the case that it is commented out or not configured properly? The SSH server sends at most ClientAliveCountMax messages during a SSH session and waits for a response from the SSH client. The option ClientAliveInterval configures timeout after each ClientAliveCountMax message. If the SSH server does not receive a response from the client, then the connection is considered idle and terminated. To ensure the SSH idle timeout occurs precisely when the ClientAliveInterval is set, set the ClientAliveCountMax to value of 0. RHEL-08-010200 sshd_set_keepalive_0
V-244525 1133 medium The RHEL 8 SSH daemon must be configured with a timeout interval. Terminating an idle ssh session within a short time period reduces the window of opportunity for unauthorized personnel to take control of a management session enabled on the console or console port that has been let unattended. Run the following command to see what the timeout interval is: $ sudo grep ClientAliveInterval /etc/ssh/sshd_config If properly configured, the output should be: ClientAliveInterval Is it the case that it is commented out or not configured properly? SSH allows administrators to set an idle timeout interval. After this interval has passed, the idle user will be automatically logged out.

To set an idle timeout interval, edit the following line in /etc/ssh/sshd_config as follows:
ClientAliveInterval 


The timeout interval is given in seconds. For example, have a timeout of 10 minutes, set interval to 600.

If a shorter timeout has already been set for the login shell, that value will preempt any SSH setting made in /etc/ssh/sshd_config. Keep in mind that some processes may stop SSH from correctly detecting that the user is idle.
RHEL-08-010201 sshd_set_idle_timeout
V-230245 1314 medium The RHEL 8 /var/log/messages file must have mode 0640 or less permissive. The /var/log/messages file contains logs of error messages in the system and should only be accessed by authorized personnel. To check the permissions of /var/log/messages, run the command: $ ls -l /var/log/messages If properly configured, the output should indicate the following permissions: -rw-r----- Is it the case that /var/log/messages has unix mode -rw-r-----? To properly set the permissions of /var/log/messages, run the command:
$ sudo chmod 0640 /var/log/messages
RHEL-08-010210 file_permissions_var_log_messages
V-230246 1314 medium The RHEL 8 /var/log/messages file must be owned by root. The /var/log/messages file contains logs of error messages in the system and should only be accessed by authorized personnel. To check the ownership of /var/log/messages, run the command: $ ls -lL /var/log/messages If properly configured, the output should indicate the following owner: root Is it the case that /var/log/messages has owner root? To properly set the owner of /var/log/messages, run the command:
$ sudo chown root /var/log/messages 
RHEL-08-010220 file_owner_var_log_messages
V-230247 1314 medium The RHEL 8 /var/log/messages file must be group-owned by root. The /var/log/messages file contains logs of error messages in the system and should only be accessed by authorized personnel. To check the group ownership of /var/log/messages, run the command: $ ls -lL /var/log/messages If properly configured, the output should indicate the following group-owner: root Is it the case that /var/log/messages has group owner root? To properly set the group owner of /var/log/messages, run the command:
$ sudo chgrp root /var/log/messages
RHEL-08-010230 file_groupowner_var_log_messages
V-230248 1314 medium The RHEL 8 /var/log directory must have mode 0755 or less permissive. The /var/log directory contains files with logs of error messages in the system and should only be accessed by authorized personnel. To check the permissions of /var/log, run the command: $ ls -l /var/log If properly configured, the output should indicate the following permissions: drwxr-xr-x Is it the case that /var/log has unix mode drwxr-xr-x? To properly set the permissions of /var/log, run the command:
$ sudo chmod 0755 /var/log
RHEL-08-010240 file_permissions_var_log
V-230249 1314 medium The RHEL 8 /var/log directory must be owned by root. The /var/log directory contains files with logs of error messages in the system and should only be accessed by authorized personnel. To check the ownership of /var/log, run the command: $ ls -lL /var/log If properly configured, the output should indicate the following owner: root Is it the case that /var/log has owner root? To properly set the owner of /var/log, run the command:
$ sudo chown root /var/log 
RHEL-08-010250 file_owner_var_log
V-230250 1314 medium The RHEL 8 /var/log directory must be group-owned by root. The /var/log directory contains files with logs of error messages in the system and should only be accessed by authorized personnel. To check the group ownership of /var/log, run the command: $ ls -lL /var/log If properly configured, the output should indicate the following group-owner: root Is it the case that /var/log has group owner root? To properly set the group owner of /var/log, run the command:
$ sudo chgrp root /var/log
RHEL-08-010260 file_groupowner_var_log
V-244526 medium The RHEL 8 SSH daemon must be configured to use system-wide crypto policies. RHEL-08-010287 Missing Rule
V-230251 1453 medium The RHEL 8 SSH server must be configured to use only Message Authentication Codes (MACs) employing FIPS 140-2 validated cryptographic hash algorithms. Overriding the system crypto policy makes the behavior of the OpenSSH server violate expectations, and makes system configuration more fragmented. To verify if the OpenSSH server uses defined MACs in the Crypto Policy, run: $ grep -Po '(-oMACs=\S+)' /etc/crypto-policies/back-ends/opensshserver.config and verify that the line matches: -oMACS=hmac-sha2-512,hmac-sha2-256 Is it the case that Crypto Policy for OpenSSH Server is not configured correctly? Crypto Policies provide a centralized control over crypto algorithms usage of many packages. OpenSSH is supported by system crypto policy, but the OpenSSH configuration may be set up incorrectly. To check that Crypto Policies settings are configured correctly, ensure that /etc/crypto-policies/back-ends/opensshserver.config contains the following text and is not commented out: -oMACS=hmac-sha2-512,hmac-sha2-256 RHEL-08-010290 harden_sshd_macs_opensshserver_conf_crypto_policy
V-230252 1453 medium The RHEL 8 operating system must implement DoD-approved encryption to protect the confidentiality of SSH server connections. Overriding the system crypto policy makes the behavior of the OpenSSH server violate expectations, and makes system configuration more fragmented. By specifying a cipher list with the order of ciphers being in a “strongest to weakest” orientation, the system will automatically attempt to use the strongest cipher for securing SSH connections. To verify if the OpenSSH server uses defined ciphers in the Crypto Policy, run: $ grep -Po '(-oCiphers=\S+)' /etc/crypto-policies/back-ends/opensshserver.config and verify that the line matches: -oCiphers= Is it the case that Crypto Policy for OpenSSH Server is not configured correctly? Crypto Policies provide a centralized control over crypto algorithms usage of many packages. OpenSSH is supported by system crypto policy, but the OpenSSH configuration may be set up incorrectly. To check that Crypto Policies settings for ciphers are configured correctly, ensure that /etc/crypto-policies/back-ends/opensshserver.config contains the following text and is not commented out:
-oCiphers=
RHEL-08-010291 harden_sshd_ciphers_opensshserver_conf_crypto_policy
V-230253 366 low RHEL 8 must ensure the SSH server uses strong entropy. SSH implementation in RHEL8 uses the openssl library, which doesn't use high-entropy sources by default. Randomness is needed to generate data-encryption keys, and as plaintext padding and initialization vectors in encryption algorithms, and high-quality entropy elliminates the possibility that the output of the random number generator used by SSH would be known to potential attackers. To determine whether the SSH service is configured to use strong entropy seed, run $ sudo grep SSH_USE_STRONG_RNG /etc/sysconfig/sshd If a line indicating that SSH_USE_STRONG_RNG is set to 32 is returned, then the option is set correctly. Is it the case that The SSH_USE_STRONG_RNG is not set to 32 in /etc/sysconfig/sshd? To set up SSH server to use entropy from a high-quality source, edit the /etc/sysconfig/sshd file. The SSH_USE_STRONG_RNG configuration value determines how many bytes of entropy to use, so make sure that the file contains line
SSH_USE_STRONG_RNG=32
RHEL-08-010292 sshd_use_strong_rng
V-230254 1453 medium The RHEL 8 operating system must implement DoD-approved encryption in the OpenSSL package. Overriding the system crypto policy makes the behavior of the Java runtime violates expectations, and makes system configuration more fragmented. To verify that OpenSSL uses the system crypto policy, check out that the OpenSSL config file /etc/pki/tls/openssl.cnf contains the [ crypto_policy ] section with the .include /etc/crypto-policies/back-ends/opensslcnf.config directive: grep '\.include\s* /etc/crypto-policies/back-ends/opensslcnf.config$' /etc/pki/tls/openssl.cnf. Is it the case that the OpenSSL config file doesn't contain the whole section, or that the section doesn't have the <pre>.include /etc/crypto-policies/back-ends/opensslcnf.config</pre> directive? Crypto Policies provide a centralized control over crypto algorithms usage of many packages. OpenSSL is supported by crypto policy, but the OpenSSL configuration may be set up to ignore it. To check that Crypto Policies settings are configured correctly, you have to examine the OpenSSL config file available under /etc/pki/tls/openssl.cnf. This file has the ini format, and it enables crypto policy support if there is a [ crypto_policy ] section that contains the .include /etc/crypto-policies/back-ends/opensslcnf.config directive. RHEL-08-010293 configure_openssl_crypto_policy
V-230255 1453 medium The RHEL 8 operating system must implement DoD-approved TLS encryption in the OpenSSL package. Without cryptographic integrity protections, information can be altered by unauthorized users without detection. To verify if the OpenSSL uses defined TLS Crypto Policy, run: $ grep -P '^(TLS\.)?MinProtocol' /etc/crypto-policies/back-ends/opensslcnf.config and verify that the value is TLSv1.2 Is it the case that cryptographic policy for openssl is not configured or is configured incorrectly? Crypto Policies are means of enforcing certain cryptographic settings for selected applications including OpenSSL. OpenSSL is by default configured to modify its configuration based on currently configured Crypto Policy. Editing the Crypto Policy back-end is not recommended. Check the crypto-policies(7) man page and choose a policy that configures TLS protocol to version 1.2 or higher, for example DEFAULT, FUTURE or FIPS policy. Or create and apply a custom policy that restricts minimum TLS version to 1.2. RHEL-08-010294 configure_openssl_tls_crypto_policy
V-230256 1453 medium The RHEL 8 operating system must implement DoD-approved TLS encryption in the GnuTLS package. Overriding the system crypto policy makes the behavior of the GnuTLS library violate expectations, and makes system configuration more fragmented. To verify if GnuTLS uses defined DoD-approved TLS Crypto Policy, run: $ grep '+VERS-ALL:-VERS-DTLS0.9:-VERS-SSL3.0:-VERS-TLS1.0:-VERS-TLS1.1:-VERS-DTLS1.0' /etc/crypto-policies/back-ends/gnutls.config and verify that a match exists. Is it the case that cryptographic policy for gnutls is not configured or is configured incorrectly? Crypto Policies provide a centralized control over crypto algorithms usage of many packages. GnuTLS is supported by system crypto policy, but the GnuTLS configuration may be set up to ignore it. To check that Crypto Policies settings are configured correctly, ensure that /etc/crypto-policies/back-ends/gnutls.config contains the following line and is not commented out: +VERS-ALL:-VERS-DTLS0.9:-VERS-SSL3.0:-VERS-TLS1.0:-VERS-TLS1.1:-VERS-DTLS1.0 RHEL-08-010295 configure_gnutls_tls_crypto_policy
V-230257 1499 medium RHEL 8 system commands must have mode 0755 or less permissive. System binaries are executed by privileged users, as well as system services, and restrictive permissions are necessary to ensure execution of these programs cannot be co-opted. System executables are stored in the following directories by default: /bin /sbin /usr/bin /usr/libexec /usr/local/bin /usr/local/sbin /usr/sbin To find system executables that are group-writable or world-writable, run the following command for each directory DIR which contains system executables: $ sudo find -L DIR -perm /022 -type f Is it the case that any system executables are found to be group or world writable? System executables are stored in the following directories by default:
/bin
/sbin
/usr/bin
/usr/libexec
/usr/local/bin
/usr/local/sbin
/usr/sbin
All files in these directories should not be group-writable or world-writable. If any file FILE in these directories is found to be group-writable or world-writable, correct its permission with the following command:
$ sudo chmod go-w FILE
RHEL-08-010300 file_permissions_binary_dirs
V-230258 1499 medium RHEL 8 system commands must be owned by root. System binaries are executed by privileged users as well as system services, and restrictive permissions are necessary to ensure that their execution of these programs cannot be co-opted. System executables are stored in the following directories by default: /bin /sbin /usr/bin /usr/libexec /usr/local/bin /usr/local/sbin /usr/sbin To find system executables that are not owned by root, run the following command for each directory DIR which contains system executables: $ sudo find DIR/ \! -user root Is it the case that any system executables are found to not be owned by root? System executables are stored in the following directories by default:
/bin
/sbin
/usr/bin
/usr/libexec
/usr/local/bin
/usr/local/sbin
/usr/sbin
All files in these directories should be owned by the root user. If any file FILE in these directories is found to be owned by a user other than root, correct its ownership with the following command:
$ sudo chown root FILE
RHEL-08-010310 file_ownership_binary_dirs
V-230259 1499 medium RHEL 8 system commands must be group-owned by root or a system account. If the operating system allows any user to make changes to software libraries, then those changes might be implemented without undergoing the appropriate testing and approvals that are part of a robust change management process. This requirement applies to operating systems with software libraries that are accessible and configurable, as in the case of interpreted languages. Software libraries also include privileged programs which execute with escalated privileges. Only qualified and authorized individuals must be allowed to obtain access to information system components for purposes of initiating changes, including upgrades and modifications. System commands are stored in the following directories: /bin /sbin /usr/bin /usr/sbin /usr/local/bin /usr/local/sbin For each of these directories, run the following command to find files not owned by root group: $ sudo find -L $DIR ! -group root -type f \; Is it the case that any of these files are not owned by root group? System commands files are stored in the following directories by default:
/bin
/sbin
/usr/bin
/usr/sbin
/usr/local/bin
/usr/local/sbin
All files in these directories should be owned by the root group. If the directory, or any file in these directories, is found to be owned by a group other than root correct its ownership with the following command:
$ sudo chgrp root FILE
RHEL-08-010320 file_groupownership_system_commands_dirs
V-230260 1499 medium RHEL 8 library files must have mode 0755 or less permissive. Files from shared library directories are loaded into the address space of processes (including privileged ones) or of the kernel itself at runtime. Restrictive permissions are necessary to protect the integrity of the system. Shared libraries are stored in the following directories: /lib /lib64 /usr/lib /usr/lib64 To find shared libraries that are group-writable or world-writable, run the following command for each directory DIR which contains shared libraries: $ sudo find -L DIR -perm /022 -type f Is it the case that any of these files are group-writable or world-writable? System-wide shared library files, which are linked to executables during process load time or run time, are stored in the following directories by default:
/lib
/lib64
/usr/lib
/usr/lib64
Kernel modules, which can be added to the kernel during runtime, are stored in /lib/modules. All files in these directories should not be group-writable or world-writable. If any file in these directories is found to be group-writable or world-writable, correct its permission with the following command:
$ sudo chmod go-w FILE
RHEL-08-010330 file_permissions_library_dirs
V-230261 1499 medium RHEL 8 library files must be owned by root. Files from shared library directories are loaded into the address space of processes (including privileged ones) or of the kernel itself at runtime. Proper ownership is necessary to protect the integrity of the system. Shared libraries are stored in the following directories: /lib /lib64 /usr/lib /usr/lib64 For each of these directories, run the following command to find files not owned by root: $ sudo find -L $DIR ! -user root -exec chown root {} \; Is it the case that any of these files are not owned by root? System-wide shared library files, which are linked to executables during process load time or run time, are stored in the following directories by default:
/lib
/lib64
/usr/lib
/usr/lib64
Kernel modules, which can be added to the kernel during runtime, are also stored in /lib/modules. All files in these directories should be owned by the root user. If the directory, or any file in these directories, is found to be owned by a user other than root correct its ownership with the following command:
$ sudo chown root FILE
RHEL-08-010340 file_ownership_library_dirs
V-230262 1499 medium RHEL 8 library files must be group-owned by root or a system account. If the operating system were to allow any user to make changes to software libraries, then those changes might be implemented without undergoing the appropriate testing and approvals that are part of a robust change management process. This requirement applies to operating systems with software libraries that are accessible and configurable, as in the case of interpreted languages. Software libraries also include privileged programs which execute with escalated privileges. Only qualified and authorized individuals must be allowed to obtain access to information system components for purposes of initiating changes, including upgrades and modifications. System-wide library files are stored in the following directories: /lib /lib64 /usr/lib /usr/lib64 To find if system-wide library files stored in these directories are not group-owned by root run the following command for each directory DIR: $ sudo find -L DIR ! -group root -type f Is it the case that system wide library files are not group owned by root? System-wide library files are stored in the following directories by default:
/lib
/lib64
/usr/lib
/usr/lib64
All system-wide shared library files should be protected from unauthorised access. If any of these files is not owned by root, correct its owner with the following command:
$ sudo chgrp root FILE
RHEL-08-010350 root_permissions_syslibrary_files
V-230263 1744 medium The RHEL 8 file integrity tool must notify the system administrator when changes to the baseline configuration or anomalies in the operation of any security functions are discovered within an organizationally defined frequency. Unauthorized changes to the baseline configuration could make the system vulnerable to various attacks or allow unauthorized access to the operating system. Changes to operating system configurations can have unintended side effects, some of which may be relevant to security.

Detecting such changes and providing an automated response can help avoid unintended, negative consequences that could ultimately affect the security state of the operating system. The operating system's Information Management Officer (IMO)/Information System Security Officer (ISSO) and System Administrators (SAs) must be notified via email and/or monitoring system trap when there is an unauthorized modification of a configuration item.
To determine that periodic AIDE execution has been scheduled, run the following command: $ grep aide /etc/crontab The output should return something similar to the following: 05 4 * * * root /usr/sbin/aide --check | /bin/mail -s "$(hostname) - AIDE Integrity Check" root@localhost The email address that the notifications are sent to can be changed by overriding . Is it the case that AIDE has not been configured or has not been configured to notify personnel of scan details? AIDE should notify appropriate personnel of the details of a scan after the scan has been run. If AIDE has already been configured for periodic execution in /etc/crontab, append the following line to the existing AIDE line:
 | /bin/mail -s "$(hostname) - AIDE Integrity Check" root@localhost
Otherwise, add the following line to /etc/crontab:
05 4 * * * root /usr/sbin/aide --check | /bin/mail -s "$(hostname) - AIDE Integrity Check" root@localhost
AIDE can be executed periodically through other means; this is merely one example.
RHEL-08-010360 aide_scan_notification
V-230264 1749 high RHEL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components from a repository without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. Changes to any software components can have significant effects on the overall security of the operating system. This requirement ensures the software has not been tampered with and that it has been provided by a trusted vendor.
Accordingly, patches, service packs, device drivers, or operating system components must be signed with a certificate recognized and approved by the organization.
Verifying the authenticity of the software prior to installation validates the integrity of the patch or upgrade received from a vendor. This ensures the software has not been tampered with and that it has been provided by a trusted vendor. Self-signed certificates are disallowed by this requirement. Certificates used to verify the software must be from an approved Certificate Authority (CA).
To determine whether yum is configured to use gpgcheck, inspect /etc/yum.conf and ensure the following appears in the [main] section: gpgcheck=1 A value of 1 indicates that gpgcheck is enabled. Absence of a gpgcheck line or a setting of 0 indicates that it is disabled. Is it the case that GPG checking is not enabled? The gpgcheck option controls whether RPM packages' signatures are always checked prior to installation. To configure yum to check package signatures before installing them, ensure the following line appears in /etc/yum.conf in the [main] section:
gpgcheck=1
RHEL-08-010370 ensure_gpgcheck_globally_activated
V-230265 1749 high RHEL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components of local packages without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. Changes to any software components can have significant effects to the overall security of the operating system. This requirement ensures the software has not been tampered and has been provided by a trusted vendor.

Accordingly, patches, service packs, device drivers, or operating system components must be signed with a certificate recognized and approved by the organization.
To verify that localpkg_gpgcheck is configured properly, run the following command: $ grep localpkg_gpgcheck /etc/yum.conf The output should return something similar to: localpkg_gpgcheck=1 Is it the case that gpgcheck is not enabled or configured correctly to verify local packages? yum should be configured to verify the signature(s) of local packages prior to installation. To configure yum to verify signatures of local packages, set the localpkg_gpgcheck to 1 in /etc/yum.conf. RHEL-08-010371 ensure_gpgcheck_local_packages
V-230266 1749 medium RHEL 8 must prevent the loading of a new kernel for later execution. Disabling kexec_load allows greater control of the kernel memory. It makes it impossible to load another kernel image after it has been disabled. The runtime status of the kernel.kexec_load_disabled kernel parameter can be queried by running the following command: $ sysctl kernel.kexec_load_disabled The output of the command should indicate a value of 1. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*kernel.kexec_load_disabled\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than kernel.kexec_load_disabled = 1 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains kernel.kexec_load_disabled = 1, and that one assignment is returned when $ grep -r kernel.kexec_load_disabled /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the kernel.kexec_load_disabled kernel parameter, run the following command:
$ sudo sysctl -w kernel.kexec_load_disabled=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
kernel.kexec_load_disabled = 1
RHEL-08-010372 sysctl_kernel_kexec_load_disabled
V-230267 2165 medium RHEL 8 must enable kernel parameters to enforce discretionary access control on symlinks. By enabling this kernel parameter, symbolic links are permitted to be followed only when outside a sticky world-writable directory, or when the UID of the link and follower match, or when the directory owner matches the symlink's owner. Disallowing such symlinks helps mitigate vulnerabilities based on insecure file system accessed by privileged programs, avoiding an exploitation vector exploiting unsafe use of open() or creat(). The runtime status of the fs.protected_symlinks kernel parameter can be queried by running the following command: $ sysctl fs.protected_symlinks The output of the command should indicate a value of 1. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*fs.protected_symlinks\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than fs.protected_symlinks = 1 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains fs.protected_symlinks = 1, and that one assignment is returned when $ grep -r fs.protected_symlinks /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the fs.protected_symlinks kernel parameter, run the following command:
$ sudo sysctl -w fs.protected_symlinks=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
fs.protected_symlinks = 1
RHEL-08-010373 sysctl_fs_protected_symlinks
V-230268 2165 medium RHEL 8 must enable kernel parameters to enforce discretionary access control on hardlinks. By enabling this kernel parameter, users can no longer create soft or hard links to files which they do not own. Disallowing such hardlinks mitigate vulnerabilities based on insecure file system accessed by privileged programs, avoiding an exploitation vector exploiting unsafe use of open() or creat(). The runtime status of the fs.protected_hardlinks kernel parameter can be queried by running the following command: $ sysctl fs.protected_hardlinks The output of the command should indicate a value of 1. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*fs.protected_hardlinks\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than fs.protected_hardlinks = 1 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains fs.protected_hardlinks = 1, and that one assignment is returned when $ grep -r fs.protected_hardlinks /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the fs.protected_hardlinks kernel parameter, run the following command:
$ sudo sysctl -w fs.protected_hardlinks=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
fs.protected_hardlinks = 1
RHEL-08-010374 sysctl_fs_protected_hardlinks
V-230269 1090 low RHEL 8 must restrict access to the kernel message buffer. Unprivileged access to the kernel syslog can expose sensitive kernel address information. The runtime status of the kernel.dmesg_restrict kernel parameter can be queried by running the following command: $ sysctl kernel.dmesg_restrict The output of the command should indicate a value of 1. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*kernel.dmesg_restrict\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than kernel.dmesg_restrict = 1 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains kernel.dmesg_restrict = 1, and that one assignment is returned when $ grep -r kernel.dmesg_restrict /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the kernel.dmesg_restrict kernel parameter, run the following command:
$ sudo sysctl -w kernel.dmesg_restrict=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
kernel.dmesg_restrict = 1
RHEL-08-010375 sysctl_kernel_dmesg_restrict
V-230270 1090 low RHEL 8 must prevent kernel profiling by unprivileged users. Kernel profiling can reveal sensitive information about kernel behaviour. The runtime status of the kernel.perf_event_paranoid kernel parameter can be queried by running the following command: $ sysctl kernel.perf_event_paranoid The output of the command should indicate a value of 2. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*kernel.perf_event_paranoid\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than kernel.perf_event_paranoid = 2 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains kernel.perf_event_paranoid = 2, and that one assignment is returned when $ grep -r kernel.perf_event_paranoid /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the kernel.perf_event_paranoid kernel parameter, run the following command:
$ sudo sysctl -w kernel.perf_event_paranoid=2
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
kernel.perf_event_paranoid = 2
RHEL-08-010376 sysctl_kernel_perf_event_paranoid
V-230271 2038 medium RHEL 8 must require users to provide a password for privilege escalation. Without re-authentication, users may access resources or perform tasks for which they do not have authorization.

When operating systems provide the capability to escalate a functional capability, it is critical that the user re-authenticate.
To determine if NOPASSWD has been configured for sudo, run the following command: $ sudo grep -ri nopasswd /etc/sudoers /etc/sudoers.d/ The command should return no output. Is it the case that nopasswd is enabled in sudo? The sudo NOPASSWD tag, when specified, allows a user to execute commands using sudo without having to authenticate. This should be disabled by making sure that the NOPASSWD tag does not exist in /etc/sudoers configuration file or any sudo configuration snippets in /etc/sudoers.d/. RHEL-08-010380 sudo_remove_nopasswd
V-230272 2038 medium RHEL 8 must require users to reauthenticate for privilege escalation. Without re-authentication, users may access resources or perform tasks for which they do not have authorization.

When operating systems provide the capability to escalate a functional capability, it is critical that the user re-authenticate.
To determine if !authenticate has not been configured for sudo, run the following command: $ sudo grep -r \!authenticate /etc/sudoers /etc/sudoers.d/ The command should return no output. Is it the case that !authenticate is enabled in sudo? The sudo !authenticate option, when specified, allows a user to execute commands using sudo without having to authenticate. This should be disabled by making sure that the !authenticate option does not exist in /etc/sudoers configuration file or any sudo configuration snippets in /etc/sudoers.d/. RHEL-08-010381 sudo_remove_no_authenticate
V-237641 366 medium RHEL 8 must restrict privilege elevation to authorized personnel. If the "sudoers" file is not configured correctly, any user defined on the system can initiate privileged actions on the target system. To determine if "sudoers" file, restricts sudo access, run the following commands: $ sudo grep -PR '^\s*ALL\s+ALL\=\(ALL\)\s+ALL\s*$' /etc/sudoers /etc/sudoers.d/* $ sudo grep -PR '^\s*ALL\s+ALL\=\(ALL\:ALL\)\s+ALL\s*$' /etc/sudoers /etc/sudoers.d/* Both commands should return no output. Is it the case that /etc/sudoers file does not restrict sudo access to authorized personnel? The sudo command allows a user to execute programs with elevated (administrator) privileges. It prompts the user for their password and confirms your request to execute a command by checking a file, called sudoers. Restrict privileged actions by removing the following entries from the sudoers file: ALL ALL=(ALL) ALL ALL ALL=(ALL:ALL) ALL RHEL-08-010382 sudo_restrict_privilege_elevation_to_authorized
V-237642 2227 medium RHEL 8 must use the invoking user's password for privilege escalation when using "sudo". If the rootpw, targetpw, or runaspw flags are defined and not disabled, by default the operating system will prompt the invoking user for the "root" user password. Run the following command to Verify that the sudoers security policy is configured to use the invoking user's password for privilege escalation: sudo egrep -i '(!rootpw|!targetpw|!runaspw)' /etc/sudoers /etc/sudoers.d/* | grep -v '#' If no results are returned, this is a finding If "Defaults !targetpw" is not defined, this is a finding. If "Defaults !rootpw" is not defined, this is a finding. If "Defaults !runaspw" is not defined, this is a finding. Is it the case that invoke user passwd when using sudo? The sudoers security policy requires that users authenticate themselves before they can use sudo. When sudoers requires authentication, it validates the invoking user's credentials. The expected output for:
sudo egrep -i '(!rootpw|!targetpw|!runaspw)' /etc/sudoers /etc/sudoers.d/* | grep -v '#'
 /etc/sudoers:Defaults !targetpw
      /etc/sudoers:Defaults !rootpw
      /etc/sudoers:Defaults !runaspw 
RHEL-08-010383 sudoers_validate_passwd
V-237643 2038 medium RHEL 8 must require re-authentication when using the "sudo" command. Without re-authentication, users may access resources or perform tasks for which they do not have authorization.

When operating systems provide the capability to escalate a functional capability, it is critical that the user re-authenticate.
Verify the operating system requires re-authentication when using the "sudo" command to elevate privileges, run the following command: sudo grep -ri '^Defaults.*timestamp_timeout' /etc/sudoers /etc/sudoers.d The output should be: /etc/sudoers:Defaults timestamp_timeout=0 or "timestamp_timeout" is set to a positive number. Is it the case that timestamp_timeout is not set with the appropriate value for sudo? The sudo timestamp_timeout tag sets the amount of time sudo password prompt waits. The default timestamp_timeout value is 5 minutes. The timestamp_timeout should be configured by making sure that the timestamp_timeout tag exists in /etc/sudoers configuration file or any sudo configuration snippets in /etc/sudoers.d/. If the value is set to an integer less than 0, the user's time stamp will not expire and the user will not have to re-authenticate for privileged actions until the user's session is terminated. RHEL-08-010384 sudo_require_reauthentication
V-230273 1948 medium RHEL 8 must have the packages required for multifactor authentication installed. Using an authentication device, such as a CAC or token that is separate from the information system, ensures that even if the information system is compromised, that compromise will not affect credentials stored on the authentication device.

Multifactor solutions that require devices separate from information systems gaining access include, for example, hardware tokens providing time-based or challenge-response authenticators and smart cards such as the U.S. Government Personal Identity Verification card and the DoD Common Access Card.
'Run the following command to determine if the openssl-pkcs11 package is installed: $ rpm -q openssl-pkcs11' Is it the case that smartcard software is not installed? Configure the operating system to implement multifactor authentication by installing the required package with the following command: The openssl-pkcs11 package can be installed with the following command:
$ sudo yum install openssl-pkcs11
RHEL-08-010390 install_smartcard_packages
V-230274 medium RHEL 8 must implement certificate status checking for multifactor authentication. RHEL-08-010400 Missing Rule
V-230275 1953 medium RHEL 8 must accept Personal Identity Verification (PIV) credentials. Using an authentication device, such as a CAC or token that is separate from the information system, ensures that even if the information system is compromised, that compromise will not affect credentials stored on the authentication device.

Multifactor solutions that require devices separate from information systems gaining access include, for example, hardware tokens providing time-based or challenge-response authenticators and smart cards such as the U.S. Government Personal Identity Verification card and the DoD Common Access Card.
Run the following command to determine if the opensc package is installed: $ rpm -q opensc Is it the case that the package is not installed? The opensc package can be installed with the following command:
$ sudo yum install opensc
RHEL-08-010410 package_opensc_installed
V-230276 2824 medium RHEL 8 must implement non-executable data to protect its memory from unauthorized code execution. Computers with the ability to prevent this type of code execution frequently put an option in the BIOS that will allow users to turn the feature on or off at will. Reboot the system and enter the BIOS or Setup configuration menu. Navigate the BIOS configuration menu and make sure that the option is enabled. The setting may be located under a Security section. Look for Execute Disable (XD) on Intel-based systems and No Execute (NX) on AMD-based systems. RHEL-08-010420 bios_enable_execution_restrictions
V-230277 1084 medium RHEL 8 must clear the page allocator to prevent use-after-free attacks. Poisoning writes an arbitrary value to freed pages, so any modification or reference to that page after being freed or before being initialized will be detected and prevented. This prevents many types of use-after-free vulnerabilities at little performance cost. Also prevents leak of data and detection of corrupted memory. Inspect the form of default GRUB 2 command line for the Linux operating system in /etc/default/grub. If they include page_poison=1, then page poisoning is enabled at boot time. To ensure page_poison=1 is configured on all installed kernels, the following command may be used: $ sudo /sbin/grubby --update-kernel=ALL --args="page_poison=1 Is it the case that page allocator poisoning is not enabled? To enable poisoning of free pages, add the argument page_poison=1 to the default GRUB 2 command line for the Linux operating system in /etc/default/grub, in the manner below:
GRUB_CMDLINE_LINUX="page_poison=1"
RHEL-08-010421 grub2_page_poison_argument
V-230278 1084 medium RHEL 8 must disable virtual syscalls. Virtual Syscalls provide an opportunity of attack for a user who has control of the return instruction pointer. Inspect the form of default GRUB 2 command line for the Linux operating system in /etc/default/grub. If they include vsyscall=none, then virtyal syscalls are not enabled at boot time. To ensure vsyscall=none is configured on all installed kernels, the following command may be used: $ sudo /sbin/grubby --update-kernel=ALL --args="vsyscall=none Is it the case that vsyscalls are enabled? To disable use of virtual syscalls, add the argument vsyscall=none to the default GRUB 2 command line for the Linux operating system in /etc/default/grub, in the manner below:
GRUB_CMDLINE_LINUX="vsyscall=none"
RHEL-08-010422 grub2_vsyscall_argument
V-230279 1084 medium RHEL 8 must clear SLUB/SLAB objects to prevent use-after-free attacks. Poisoning writes an arbitrary value to freed objects, so any modification or reference to that object after being freed or before being initialized will be detected and prevented. This prevents many types of use-after-free vulnerabilities at little performance cost. Also prevents leak of data and detection of corrupted memory. Inspect the form of default GRUB 2 command line for the Linux operating system in /etc/default/grub. If they include slub_debug=P, then SLUB/SLAB poisoning is enabled at boot time. To ensure slub_debug=P is configured on all installed kernels, the following command may be used: $ sudo /sbin/grubby --update-kernel=ALL --args="slub_debug=P Is it the case that SLUB/SLAB poisoning is not enabled? To enable poisoning of SLUB/SLAB objects, add the argument slub_debug=P to the default GRUB 2 command line for the Linux operating system in /etc/default/grub, in the manner below:
GRUB_CMDLINE_LINUX="slub_debug=P"
RHEL-08-010423 grub2_slub_debug_argument
V-230280 2824 medium RHEL 8 must implement address space layout randomization (ASLR) to protect its memory from unauthorized code execution. Address space layout randomization (ASLR) makes it more difficult for an attacker to predict the location of attack code they have introduced into a process's address space during an attempt at exploitation. Additionally, ASLR makes it more difficult for an attacker to know the location of existing code in order to re-purpose it using return oriented programming (ROP) techniques. The runtime status of the kernel.randomize_va_space kernel parameter can be queried by running the following command: $ sysctl kernel.randomize_va_space The output of the command should indicate a value of 2. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*kernel.randomize_va_space\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than kernel.randomize_va_space = 2 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains kernel.randomize_va_space = 2, and that one assignment is returned when $ grep -r kernel.randomize_va_space /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the kernel.randomize_va_space kernel parameter, run the following command:
$ sudo sysctl -w kernel.randomize_va_space=2
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
kernel.randomize_va_space = 2
RHEL-08-010430 sysctl_kernel_randomize_va_space
V-230281 2617 low YUM must remove all software components after updated versions have been installed on RHEL 8. Previous versions of software components that are not removed from the information system after updates have been installed may be exploited by some adversaries. To verify that clean_requirements_on_remove is configured properly, run the following command: $ grep clean_requirements_on_remove /etc/yum.conf The output should return something similar to: clean_requirements_on_remove=1 Is it the case that 'clean_requirements_on_remove is not enabled or configured correctly'? yum should be configured to remove previous software components after new versions have been installed. To configure yum to remove the previous software components after updating, set the clean_requirements_on_remove to 1 in /etc/yum.conf. RHEL-08-010440 clean_components_post_updating
V-230282 2696 medium RHEL 8 must enable the SELinux targeted policy. Setting the SELinux policy to targeted or a more specialized policy ensures the system will confine processes that are likely to be targeted for exploitation, such as network or system services.

Note: During the development or debugging of SELinux modules, it is common to temporarily place non-production systems in permissive mode. In such temporary cases, SELinux policies should be developed, and once work is completed, the system should be reconfigured to .
Check the file /etc/selinux/config and ensure the following line appears: SELINUXTYPE= Is it the case that it does not? The SELinux targeted policy is appropriate for general-purpose desktops and servers, as well as systems in many other roles. To configure the system to use this policy, add or correct the following line in /etc/selinux/config:
SELINUXTYPE=
Other policies, such as mls, provide additional security labeling and greater confinement but are not compatible with many general-purpose use cases.
RHEL-08-010450 selinux_policytype
V-230283 366 high There must be no shosts.equiv files on the RHEL 8 operating system. The shosts.equiv files are used to configure host-based authentication for the system via SSH. Host-based authentication is not sufficient for preventing unauthorized access to the system, as it does not require interactive identification and authentication of a connection request, or for the use of two-factor authentication. To verify that there are no shosts.equiv files on the system, run the following command: $ find / -name shosts.equiv No output should be returned. Is it the case that these files exist? The shosts.equiv file list remote hosts and users that are trusted by the local system. To remove these files, run the following command to delete them from any location:
$ sudo rm /[path]/[to]/[file]/shosts.equiv
RHEL-08-010460 no_host_based_files
V-230284 366 high There must be no .shosts files on the RHEL 8 operating system. The .shosts files are used to configure host-based authentication for individual users or the system via SSH. Host-based authentication is not sufficient for preventing unauthorized access to the system, as it does not require interactive identification and authentication of a connection request, or for the use of two-factor authentication. To verify that there are no .shosts files on the system, run the following command: $ sudo find / -name '.shosts' No output should be returned. Is it the case that these files exist? The ~/.shosts (in each user's home directory) files list remote hosts and users that are trusted by the local system. To remove these files, run the following command to delete them from any location:
$ sudo find / -name '.shosts' -type f -delete
RHEL-08-010470 no_user_host_based_files
V-230285 366 low RHEL 8 must enable the hardware random number generator entropy gatherer service. The rngd service feeds random data from hardware device to kernel random device. Run the following command to determine the current status of the rngd service: $ systemctl is-active rngd If the service is running, it should return the following: active Is it the case that the service is not enabled? The Hardware RNG Entropy Gatherer service should be enabled. The rngd service can be enabled with the following command:
$ sudo systemctl enable rngd.service
RHEL-08-010471 service_rngd_enabled
V-244527 366 low RHEL 8 must have the packages required to use the hardware random number generator entropy gatherer service. rng-tools provides hardware random number generator tools, such as those used in the formation of x509/PKI certificates. Run the following command to determine if the rng-tools package is installed: $ rpm -q rng-tools Is it the case that the package is not installed? The rng-tools package can be installed with the following command:
$ sudo yum install rng-tools
RHEL-08-010472 package_rng-tools_installed
V-230286 366 medium The RHEL 8 SSH public host key files must have mode 0644 or less permissive. If a public host key file is modified by an unauthorized user, the SSH service may be compromised. To check the permissions of /etc/ssh/*.pub, run the command: $ ls -l /etc/ssh/*.pub If properly configured, the output should indicate the following permissions: -rw-r--r-- Is it the case that /etc/ssh/*.pub has unix mode -rw-r--r--? To properly set the permissions of /etc/ssh/*.pub, run the command:
$ sudo chmod 0644 /etc/ssh/*.pub
RHEL-08-010480 file_permissions_sshd_pub_key
V-230287 366 medium The RHEL 8 SSH private host key files must have mode 0600 or less permissive. If an unauthorized user obtains the private SSH host key file, the host could be impersonated. To check the permissions of /etc/ssh/*_key, run the command: $ ls -l /etc/ssh/*_key If properly configured, the output should indicate the following permissions: -rw-r----- Is it the case that /etc/ssh/*_key has unix mode -rw-r-----? To properly set the permissions of /etc/ssh/*_key, run the command:
$ sudo chmod 0640 /etc/ssh/*_key
RHEL-08-010490 file_permissions_sshd_private_key
V-230288 366 medium The RHEL 8 SSH daemon must perform strict mode checking of home directory configuration files. If other users have access to modify user-specific SSH configuration files, they may be able to log into the system as another user. To check if StrictModes is enabled or set correctly, run the following command: $ sudo grep StrictModes /etc/ssh/sshd_config If configured properly, output should be yes Is it the case that it is commented out or is not enabled? SSHs StrictModes option checks file and ownership permissions in the user's home directory .ssh folder before accepting login. If world- writable permissions are found, logon is rejected. To enable StrictModes in SSH, add or correct the following line in the /etc/ssh/sshd_config file:
StrictModes yes
RHEL-08-010500 sshd_enable_strictmodes
V-230289 366 medium The RHEL 8 SSH daemon must not allow compression or must only allow compression after successful authentication. If compression is allowed in an SSH connection prior to authentication, vulnerabilities in the compression software could result in compromise of the system from an unauthenticated connection, potentially with root privileges. To check if compression is enabled or set correctly, run the following command: $ sudo grep Compression /etc/ssh/sshd_config If configured properly, output should be no or delayed. Is it the case that it is commented out, or is not set to no or delayed? Compression is useful for slow network connections over long distances but can cause performance issues on local LANs. If use of compression is required, it should be enabled only after a user has authenticated; otherwise, it should be disabled. To disable compression or delay compression until after a user has successfully authenticated, add or correct the following line in the /etc/ssh/sshd_config file:
Compression 
RHEL-08-010510 sshd_disable_compression
V-230290 366 medium The RHEL 8 SSH daemon must not allow authentication using known host’s authentication. Configuring this setting for the SSH daemon provides additional assurance that remote login via SSH will require a password, even in the event of misconfiguration elsewhere. To determine how the SSH daemon's IgnoreUserKnownHosts option is set, run the following command: $ sudo grep -i IgnoreUserKnownHosts /etc/ssh/sshd_config If a line indicating yes is returned, then the required value is set. Is it the case that the required value is not set? SSH can allow system users to connect to systems if a cache of the remote systems public keys is available. This should be disabled.

To ensure this behavior is disabled, add or correct the following line in /etc/ssh/sshd_config:
IgnoreUserKnownHosts yes
RHEL-08-010520 sshd_disable_user_known_hosts
V-230291 366 medium The RHEL 8 SSH daemon must not allow Kerberos authentication, except to fulfill documented and validated mission requirements. Kerberos authentication for SSH is often implemented using GSSAPI. If Kerberos is enabled through SSH, the SSH daemon provides a means of access to the system's Kerberos implementation. Vulnerabilities in the system's Kerberos implementations may be subject to exploitation. To check if KerberosAuthentication is disabled or set correctly, run the following command: $ sudo grep KerberosAuthentication /etc/ssh/sshd_config If configured properly, output should be no Is it the case that it is commented out or is not disabled? Unless needed, SSH should not permit extraneous or unnecessary authentication mechanisms like Kerberos. To disable Kerberos authentication, add or correct the following line in the /etc/ssh/sshd_config file:
KerberosAuthentication no
RHEL-08-010521 sshd_disable_kerb_auth
V-244528 366 medium The RHEL 8 SSH daemon must not allow GSSAPI authentication, except to fulfill documented and validated mission requirements. GSSAPI authentication is used to provide additional authentication mechanisms to applications. Allowing GSSAPI authentication through SSH exposes the system's GSSAPI to remote hosts, increasing the attack surface of the system. To check if GSSAPIAuthentication is disabled or set correctly, run the following command: $ sudo grep GSSAPIAuthentication /etc/ssh/sshd_config If configured properly, output should be no Is it the case that it is commented out or is not disabled? Unless needed, SSH should not permit extraneous or unnecessary authentication mechanisms like GSSAPI. To disable GSSAPI authentication, add or correct the following line in the /etc/ssh/sshd_config file:
GSSAPIAuthentication no
RHEL-08-010522 sshd_disable_gssapi_auth
V-230292 366 low RHEL 8 must use a separate file system for /var. Ensuring that /var is mounted on its own partition enables the setting of more restrictive mount options. This helps protect system services such as daemons or other programs which use it. It is not uncommon for the /var directory to contain world-writable directories installed by other software packages. Run the following command to determine if /var is on its own partition or logical volume: $ mount | grep "on /var" If /var has its own partition or volume group, a line will be returned. Is it the case that no line is returned? The /var directory is used by daemons and other system services to store frequently-changing data. Ensure that /var has its own partition or logical volume at installation time, or migrate it using LVM. RHEL-08-010540 partition_for_var
V-230293 366 low RHEL 8 must use a separate file system for /var/log. Placing /var/log in its own partition enables better separation between log files and other files in /var/. Run the following command to determine if /var/log is on its own partition or logical volume: $ mount | grep "on /var/log" If /var/log has its own partition or volume group, a line will be returned. Is it the case that no line is returned? System logs are stored in the /var/log directory. Ensure that it has its own partition or logical volume at installation time, or migrate it using LVM. RHEL-08-010541 partition_for_var_log
V-230294 366 low RHEL 8 must use a separate file system for the system audit data path. Placing /var/log/audit in its own partition enables better separation between audit files and other files, and helps ensure that auditing cannot be halted due to the partition running out of space. Run the following command to determine if /var/log/audit is on its own partition or logical volume: $ mount | grep "on /var/log/audit" If /var/log/audit has its own partition or volume group, a line will be returned. Is it the case that no line is returned? Audit logs are stored in the /var/log/audit directory. Ensure that it has its own partition or logical volume at installation time, or migrate it later using LVM. Make absolutely certain that it is large enough to store all audit logs that will be created by the auditing daemon. RHEL-08-010542 partition_for_var_log_audit
V-230295 366 medium A separate RHEL 8 filesystem must be used for the /tmp directory. The /tmp partition is used as temporary storage by many programs. Placing /tmp in its own partition enables the setting of more restrictive mount options, which can help protect programs which use it. Run the following command to determine if /tmp is on its own partition or logical volume: $ mount | grep "on /tmp" If /tmp has its own partition or volume group, a line will be returned. Is it the case that no line is returned? The /tmp directory is a world-writable directory used for temporary file storage. Ensure it has its own partition or logical volume at installation time, or migrate it using LVM. RHEL-08-010543 partition_for_tmp
V-244529 366 medium RHEL 8 must use a separate file system for /var/tmp. The /var/tmp partition is used as temporary storage by many programs. Placing /var/tmp in its own partition enables the setting of more restrictive mount options, which can help protect programs which use it. Run the following command to determine if /var/tmp is on its own partition or logical volume: $ mount | grep "on /var/tmp" If /var/tmp has its own partition or volume group, a line will be returned. Is it the case that no line is returned? The /var/tmp directory is a world-writable directory used for temporary file storage. Ensure it has its own partition or logical volume at installation time, or migrate it using LVM. RHEL-08-010544 partition_for_var_tmp
V-230296 770 medium RHEL 8 must not permit direct logons to the root account using remote access via SSH. Even though the communications channel may be encrypted, an additional layer of security is gained by extending the policy of not logging directly on as root. In addition, logging in with a user-specific account provides individual accountability of actions performed on the system and also helps to minimize direct attack attempts on root's password. To determine how the SSH daemon's PermitRootLogin option is set, run the following command: $ sudo grep -i PermitRootLogin /etc/ssh/sshd_config If a line indicating no is returned, then the required value is set. Is it the case that the required value is not set? The root user should never be allowed to login to a system directly over a network. To disable root login via SSH, add or correct the following line in /etc/ssh/sshd_config:
PermitRootLogin no
RHEL-08-010550 sshd_disable_root_login
V-230297 medium The auditd service must be running in RHEL 8. RHEL-08-010560 Missing Rule
V-230298 366 medium The rsyslog service must be running in RHEL 8. The rsyslog service must be running in order to provide logging services, which are essential to system administration. Run the following command to determine the current status of the rsyslog service: $ systemctl is-active rsyslog If the service is running, it should return the following: active Is it the case that ? The rsyslog service provides syslog-style logging by default on AlmaLinux 8. The rsyslog service can be enabled with the following command:
$ sudo systemctl enable rsyslog.service
RHEL-08-010561 service_rsyslog_enabled
V-230299 366 medium RHEL 8 must prevent files with the setuid and setgid bit set from being executed on file systems that contain user home directories. The presence of SUID and SGID executables should be tightly controlled. Users should not be able to execute SUID or SGID binaries from user home directory partitions. To verify the nosuid option is configured for the /home mount point, run the following command: $ mount | grep '\s/home\s' The output should show the corresponding mount point along with the nosuid setting in parentheses. Is it the case that the is not present in the output line, or there is no output line at all? The nosuid mount option can be used to prevent execution of setuid programs in /home. The SUID and SGID permissions should not be required in these user data directories. Add the nosuid option to the fourth column of /etc/fstab for the line which controls mounting of /home. RHEL-08-010570 mount_option_home_nosuid
V-230300 366 medium RHEL 8 must prevent files with the setuid and setgid bit set from being executed on the /boot directory. The presence of SUID and SGID executables should be tightly controlled. Users should not be able to execute SUID or SGID binaries from boot partitions. To verify the nosuid option is configured for the /boot mount point, run the following command: $ mount | grep '\s/boot\s' The output should show the corresponding mount point along with the nosuid setting in parentheses. Is it the case that the is not present in the output line, or there is no output line at all? The nosuid mount option can be used to prevent execution of setuid programs in /boot. The SUID and SGID permissions should not be required on the boot partition. Add the nosuid option to the fourth column of /etc/fstab for the line which controls mounting of /boot. RHEL-08-010571 mount_option_boot_nosuid
V-244530 medium RHEL 8 must prevent files with the setuid and setgid bit set from being executed on the /boot/efi directory. RHEL-08-010572 Missing Rule
V-230301 366 medium RHEL 8 must prevent special devices on non-root local partitions. The nodev mount option prevents files from being interpreted as character or block devices. The only legitimate location for device files is the /dev directory located on the root partition. The only exception to this is chroot jails, for which it is not advised to set nodev on these filesystems. To verify the nodev option is configured for non-root local partitions, run the following command: $ mount | grep '^/dev\S* on /\S' | grep --invert-match 'nodev' The output shows local non-root partitions mounted without the nodev option, and there should be no output at all. Is it the case that some mounts appear among output lines? The nodev mount option prevents files from being interpreted as character or block devices. Legitimate character and block devices should exist only in the /dev directory on the root partition or within chroot jails built for system services. Add the nodev option to the fourth column of /etc/fstab for the line which controls mounting of any non-root local partitions. RHEL-08-010580 mount_option_nodev_nonroot_local_partitions
V-230302 366 medium RHEL 8 must prevent code from being executed on file systems that contain user home directories. The /home directory contains data of individual users. Binaries in this directory should not be considered as trusted and users should not be able to execute them. To verify the noexec option is configured for the /home mount point, run the following command: $ mount | grep '\s/home\s' The output should show the corresponding mount point along with the noexec setting in parentheses. Is it the case that the is not present in the output line, or there is no output line at all? The noexec mount option can be used to prevent binaries from being executed out of /home. Add the noexec option to the fourth column of /etc/fstab for the line which controls mounting of /home. RHEL-08-010590 mount_option_home_noexec
V-230303 366 medium RHEL 8 must prevent special devices on file systems that are used with removable media. The only legitimate location for device files is the /dev directory located on the root partition. An exception to this is chroot jails, and it is not advised to set nodev on partitions which contain their root filesystems. The nodev mount option prevents files from being interpreted as character or block devices. Legitimate character and block devices should exist only in the /dev directory on the root partition or within chroot jails built for system services. Add the nodev option to the fourth column of /etc/fstab for the line which controls mounting of any removable media partitions. RHEL-08-010600 mount_option_nodev_removable_partitions
V-230304 366 medium RHEL 8 must prevent code from being executed on file systems that are used with removable media. Allowing users to execute binaries from removable media such as USB keys exposes the system to potential compromise. To verify that binaries cannot be directly executed from removable media, run the following command: $ grep -v noexec /etc/fstab The resulting output will show partitions which do not have the noexec flag. Verify all partitions in the output are not removable media. Is it the case that removable media partitions are present? The noexec mount option prevents the direct execution of binaries on the mounted filesystem. Preventing the direct execution of binaries from removable media (such as a USB key) provides a defense against malicious software that may be present on such untrusted media. Add the noexec option to the fourth column of /etc/fstab for the line which controls mounting of any removable media partitions. RHEL-08-010610 mount_option_noexec_removable_partitions
V-230305 366 medium RHEL 8 must prevent files with the setuid and setgid bit set from being executed on file systems that are used with removable media. The presence of SUID and SGID executables should be tightly controlled. Allowing users to introduce SUID or SGID binaries from partitions mounted off of removable media would allow them to introduce their own highly-privileged programs. The nosuid mount option prevents set-user-identifier (SUID) and set-group-identifier (SGID) permissions from taking effect. These permissions allow users to execute binaries with the same permissions as the owner and group of the file respectively. Users should not be allowed to introduce SUID and SGID files into the system via partitions mounted from removeable media. Add the nosuid option to the fourth column of /etc/fstab for the line which controls mounting of any removable media partitions. RHEL-08-010620 mount_option_nosuid_removable_partitions
V-230306 366 medium RHEL 8 must prevent code from being executed on file systems that are imported via Network File System (NFS). The noexec mount option causes the system not to execute binary files. This option must be used for mounting any file system not containing approved binary files as they may be incompatible. Executing files from untrusted file systems increases the opportunity for unprivileged users to attain unauthorized administrative access. To verify the noexec option is configured for all NFS mounts, run the following command: $ mount | grep nfs All NFS mounts should show the noexec setting in parentheses. This is not applicable if NFS is not implemented. Is it the case that the setting does not show? Add the noexec option to the fourth column of /etc/fstab for the line which controls mounting of any NFS mounts. RHEL-08-010630 mount_option_noexec_remote_filesystems
V-230307 366 medium RHEL 8 must prevent special devices on file systems that are imported via Network File System (NFS). Legitimate device files should only exist in the /dev directory. NFS mounts should not present device files to users. To verify the nodev option is configured for all NFS mounts, run the following command: $ mount | grep nfs All NFS mounts should show the nodev setting in parentheses. This is not applicable if NFS is not implemented. Is it the case that the setting does not show? Add the nodev option to the fourth column of /etc/fstab for the line which controls mounting of any NFS mounts. RHEL-08-010640 mount_option_nodev_remote_filesystems
V-230308 366 medium RHEL 8 must prevent files with the setuid and setgid bit set from being executed on file systems that are imported via Network File System (NFS). NFS mounts should not present suid binaries to users. Only vendor-supplied suid executables should be installed to their default location on the local filesystem. To verify the nosuid option is configured for all NFS mounts, run the following command: $ mount | grep nfs All NFS mounts should show the nosuid setting in parentheses. This is not applicable if NFS is not implemented. Is it the case that the setting does not show? Add the nosuid option to the fourth column of /etc/fstab for the line which controls mounting of any NFS mounts. RHEL-08-010650 mount_option_nosuid_remote_filesystems
V-230309 366 medium Local RHEL 8 initialization files must not execute world-writable programs. If user start-up files execute world-writable programs, especially in unprotected directories, they could be maliciously modified to destroy user files or otherwise compromise the system at the user level. If the system is compromised at the user level, it is easier to elevate privileges to eventually compromise the system at the root and network level. To verify that local initialization files do not execute world-writable programs, execute the following command: $ sudo find /home -perm -002 -type f -name ".[^.]*" -exec ls -ld {} \; There should be no output. Is it the case that files are executing world-writable programs? Set the mode on files being executed by the user initialization files with the following command:
$ sudo chmod 0755 FILE
RHEL-08-010660 accounts_user_dot_no_world_writable_programs
V-230310 366 medium RHEL 8 must disable kernel dumps unless needed. Kernel core dumps may contain the full contents of system memory at the time of the crash. Kernel core dumps consume a considerable amount of disk space and may result in denial of service by exhausting the available space on the target file system partition. Unless the system is used for kernel development or testing, there is little need to run the kdump service. To check that the kdump service is disabled in system boot configuration, run the following command: $ systemctl is-enabled kdump Output should indicate the kdump service has either not been installed, or has been disabled at all runlevels, as shown in the example below: $ systemctl is-enabled kdump disabled Run the following command to verify kdump is not active (i.e. not running) through current runtime configuration: $ systemctl is-active kdump If the service is not running the command will return the following output: inactive The service will also be masked, to check that the kdump is masked, run the following command: $ systemctl show kdump | grep "LoadState\|UnitFileState" If the service is masked the command will return the following outputs: LoadState=masked UnitFileState=masked Is it the case that ? The kdump service provides a kernel crash dump analyzer. It uses the kexec system call to boot a secondary kernel ("capture" kernel) following a system crash, which can load information from the crashed kernel for analysis. The kdump service can be disabled with the following command:
$ sudo systemctl mask --now kdump.service
RHEL-08-010670 service_kdump_disabled
V-230311 366 medium RHEL 8 must disable the kernel.core_pattern. A core dump includes a memory image taken at the time the operating system terminates an application. The memory image could contain sensitive data and is generally useful only for developers trying to debug problems. The runtime status of the kernel.core_pattern kernel parameter can be queried by running the following command: $ sysctl kernel.core_pattern The output of the command should indicate a value of |/bin/false. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*kernel.core_pattern\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than kernel.core_pattern = |/bin/false are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains kernel.core_pattern = |/bin/false, and that one assignment is returned when $ grep -r kernel.core_pattern /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the kernel.core_pattern kernel parameter, run the following command:
$ sudo sysctl -w kernel.core_pattern=|/bin/false
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
kernel.core_pattern = |/bin/false
RHEL-08-010671 sysctl_kernel_core_pattern
V-230312 366 medium RHEL 8 must disable acquiring, saving, and processing core dumps. A core dump includes a memory image taken at the time the operating system terminates an application. The memory image could contain sensitive data and is generally useful only for developers trying to debug problems. To verify that acquiring, saving, and processing core dumps is disabled, run the following command: $ systemctl status systemd-coredump.socket The output should be similar to: ● systemd-coredump.socket Loaded: masked (Reason: Unit systemd-coredump.socket is masked.) Active: inactive (dead) ... Is it the case that unit systemd-coredump.socket is not masked or running? The systemd-coredump.socket unit is a socket activation of the systemd-coredump@.service which processes core dumps. By masking the unit, core dump processing is disabled. RHEL-08-010672 service_systemd-coredump_disabled
V-230313 366 medium RHEL 8 must disable core dumps for all users. A core dump includes a memory image taken at the time the operating system terminates an application. The memory image could contain sensitive data and is generally useful only for developers trying to debug problems. To verify that core dumps are disabled for all users, run the following command: $ grep core /etc/security/limits.conf The output should be: * hard core 0 Is it the case that it is not? To disable core dumps for all users, add the following line to /etc/security/limits.conf, or to a file within the /etc/security/limits.d/ directory:
*     hard   core    0
RHEL-08-010673 disable_users_coredumps
V-230314 366 medium RHEL 8 must disable storing core dumps. A core dump includes a memory image taken at the time the operating system terminates an application. The memory image could contain sensitive data and is generally useful only for developers or system operators trying to debug problems. Enabling core dumps on production systems is not recommended, however there may be overriding operational requirements to enable advanced debuging. Permitting temporary enablement of core dumps during such situations should be reviewed through local needs and policy. To verify that storing core dumps are disabled, run the following command: $ grep Storage /etc/systemd/coredump.conf The output should be: Storage=none Is it the case that Storage is not set to none? The Storage option in [Coredump] section of /etc/systemd/coredump.conf can be set to none to disable storing core dumps permanently. RHEL-08-010674 coredump_disable_storage
V-230315 366 medium RHEL 8 must disable core dump backtraces. A core dump includes a memory image taken at the time the operating system terminates an application. The memory image could contain sensitive data and is generally useful only for developers or system operators trying to debug problems. Enabling core dumps on production systems is not recommended, however there may be overriding operational requirements to enable advanced debuging. Permitting temporary enablement of core dumps during such situations should be reviewed through local needs and policy. To verify that logging core dump backtraces is disabled, run the following command: $ grep ProcessSizeMax /etc/systemd/coredump.conf The output should be: ProcessSizeMax=0 Is it the case that ProcessSizeMax is not set to zero? The ProcessSizeMax option in [Coredump] section of /etc/systemd/coredump.conf specifies the maximum size in bytes of a core which will be processed. Core dumps exceeding this size may be stored, but the backtrace will not be generated. RHEL-08-010675 coredump_disable_backtraces
V-230316 366 medium For RHEL 8 systems using Domain Name Servers (DNS) resolution, at least two name servers must be configured. To provide availability for name resolution services, multiple redundant name servers are mandated. A failure in name resolution could lead to the failure of security functions requiring name resolution, which may include time synchronization, centralized authentication, and remote system logging. To verify that DNS servers have been configured properly, perform the following: $ sudo grep nameserver /etc/resolv.conf The output should return more than one nameserver entry. Is it the case that it does not exist or is not properly configured or less than 2 'nameserver' entries exist? Multiple Domain Name System (DNS) Servers should be configured in /etc/resolv.conf. This provides redundant name resolution services in the event that a domain server crashes. To configure the system to contain as least 2 DNS servers, add a corresponding nameserver ip_address entry in /etc/resolv.conf for each DNS server where ip_address is the IP address of a valid DNS server. For example:
search example.com
nameserver 192.168.0.1
nameserver 192.168.0.2
RHEL-08-010680 network_configure_name_resolution
V-230317 366 medium Executable search paths within the initialization files of all local interactive RHEL 8 users must only contain paths that resolve to the system default or the users home directory. The executable search path (typically the PATH environment variable) contains a list of directories for the shell to search to find executables. If this path includes the current working directory (other than the users home directory), executables in these directories may be executed instead of system commands. This variable is formatted as a colon-separated list of directories. If there is an empty entry, such as a leading or trailing colon or two consecutive colons, this is interpreted as the current working directory. If deviations from the default system search path for the local interactive user are required, they must be documented with the Information System Security Officer (ISSO). To verify that all interactive user initialization files executable search path statements do not contain statements that will reference a working directory other than the users home directory, run the following command: $ sudo grep -r PATH /home/ Inspect the output for any PATH is references directories outside the home directory. Is it the case that paths contain more than local home directories? Ensure that all interactive user initialization files executable search path statements do not contain statements that will reference a working directory other than the users home directory. RHEL-08-010690 accounts_user_home_paths_only
V-230318 366 medium All RHEL 8 world-writable directories must be owned by root, sys, bin, or an application user. Allowing a user account to own a world-writable directory is undesirable because it allows the owner of that directory to remove or replace any files that may be placed in the directory by other users. The following command will discover and print world-writable directories that are not owned by root. Run it once for each local partition PART: $ sudo find PART -xdev -type d -perm -0002 -uid +0 -print Is it the case that there is output? All directories in local partitions which are world-writable should be owned by root. If any world-writable directories are not owned by root, this should be investigated. Following this, the files should be deleted or assigned to root user. RHEL-08-010700 dir_perms_world_writable_root_owned
V-230319 medium All RHEL 8 world-writable directories must be group-owned by root, sys, bin, or an application group. RHEL-08-010710 Missing Rule
V-230320 366 medium All RHEL 8 local interactive users must have a home directory assigned in the /etc/passwd file. If local interactive users are not assigned a valid home directory, there is no place for the storage and control of files they should own. To verify interactive users on the system have a home directory assigned, run the following command: $ sudo awk -F":" '{print $1 ":" $6}' /etc/passwd Inspect the output and verify that all interactive users have a home directory defined. Is it the case that users home directory is not defined? Assign home directories to all interactive users that currently do not have a home directory assigned. RHEL-08-010720 accounts_user_interactive_home_directory_defined
V-230321 366 medium All RHEL 8 local interactive user home directories must have mode 0750 or less permissive. Excessive permissions on local interactive user home directories may allow unauthorized access to user files by other users. To verify the assigned home directory of all interactive user home directories have a mode of 0750 or less permissive, run the following command: $ sudo ls -l /home Inspect the output for any directories with incorrect permissions. Is it the case that they are more permissive? Change the mode of interactive users home directories to 0750. To change the mode of interactive users home directory, use the following command:
$ sudo chmod 0750 /home/USER
RHEL-08-010730 file_permissions_home_directories
V-244531 medium All RHEL 8 local interactive user home directory files must have mode 0750 or less permissive. RHEL-08-010731 Missing Rule
V-230322 366 medium All RHEL 8 local interactive user home directories must be group-owned by the home directory owner’s primary group. If the Group Identifier (GID) of a local interactive users home directory is not the same as the primary GID of the user, this would allow unauthorized access to the users files, and users that share the same group may not be able to access files that they legitimately should. To verify the assigned home directory of all interactive users is group- owned by that users primary GID, run the following command: # ls -ld $(awk -F: '($3>=1000)&&($7 !~ /nologin/){print $6}' /etc/passwd) Is it the case that the group ownership is incorrect? Change the group owner of interactive users home directory to the group found in /etc/passwd. To change the group owner of interactive users home directory, use the following command:
$ sudo chgrp USER_GROUP /home/USER
RHEL-08-010740 file_groupownership_home_directories
V-244532 medium RHEL 8 must be configured so that all files and directories contained in local interactive user home directories are group-owned by a group of which the home directory owner is a member. RHEL-08-010741 Missing Rule
V-230323 366 medium All RHEL 8 local interactive user home directories defined in the /etc/passwd file must exist. If a local interactive user has a home directory defined that does not exist, the user may be given access to the / directory as the current working directory upon logon. This could create a Denial of Service because the user would not be able to access their logon configuration files, and it may give them visibility to system files they normally would not be able to access. To verify the assigned home directory of all interactive users on the system exist, run the following command: $ sudo pwck -r The output should not return any interactive users. Is it the case that users home directory does not exist? Create home directories to all interactive users that currently do not have a home directory assigned. Use the following commands to create the user home directory assigned in /etc/passwd:
$ sudo mkdir /home/USER
RHEL-08-010750 accounts_user_interactive_home_directory_exists
V-230324 366 medium All RHEL 8 local interactive user accounts must be assigned a home directory upon creation. If local interactive users are not assigned a valid home directory, there is no place for the storage and control of files they should own. Check if the system is configured to create home directories for local interactive users with the following command: $ sudo grep create_home /etc/login.defs Is it the case that the value of CREATE_HOME is not set to yes, is missing, or the line is commented out? All local interactive user accounts, upon creation, should be assigned a home directory.

Configure the operating system to assign home directories to all new local interactive users by setting the CREATE_HOME parameter in /etc/login.defs to yes as follows:

CREATE_HOME yes
RHEL-08-010760 accounts_have_homedir_login_defs
V-230325 366 medium All RHEL 8 local initialization files must have mode 0740 or less permissive. Local initialization files are used to configure the user's shell environment upon logon. Malicious modification of these files could compromise accounts upon logon. To verify that all user initialization files have a mode of 0740 or less permissive, run the following command: $ sudo find /home -type f -name '\.*' \( -perm -0002 -o -perm -0020 \) There should be no output. Is it the case that they are not 0740 or more permissive? Set the mode of the user initialization files to 0740 with the following command:
$ sudo chmod 0740 /home/USER/.INIT_FILE
RHEL-08-010770 file_permission_user_init_files
V-230326 366 medium All RHEL 8 local files and directories must have a valid owner. Unowned files do not directly imply a security problem, but they are generally a sign that something is amiss. They may be caused by an intruder, by incorrect software installation or draft software removal, or by failure to remove all files belonging to a deleted account. The files should be repaired so they will not cause problems when accounts are created in the future, and the cause should be discovered and addressed. The following command will discover and print any files on local partitions which do not belong to a valid user. $ df --local -P | awk {'if (NR!=1) print $6'} | sudo xargs -I '{}' find '{}' -xdev -nouser Either remove all files and directories from the system that do not have a valid user, or assign a valid user to all unowned files and directories on the system with the chown command: $ sudo chown user file Is it the case that files exist that are not owned by a valid user? If any files are not owned by a user, then the cause of their lack of ownership should be investigated. Following this, the files should be deleted or assigned to an appropriate user. The following command will discover and print any files on local partitions which do not belong to a valid user:
$ df --local -P | awk {'if (NR!=1) print $6'} | sudo xargs -I '{}' find '{}' -xdev -nouser
To search all filesystems on a system including network mounted filesystems the following command can be run manually for each partition:
$ sudo find PARTITION -xdev -nouser
RHEL-08-010780 no_files_unowned_by_user
V-230327 366 medium All RHEL 8 local files and directories must have a valid group owner. Unowned files do not directly imply a security problem, but they are generally a sign that something is amiss. They may be caused by an intruder, by incorrect software installation or draft software removal, or by failure to remove all files belonging to a deleted account. The files should be repaired so they will not cause problems when accounts are created in the future, and the cause should be discovered and addressed. The following command will discover and print any files on local partitions which do not belong to a valid group. $ df --local -P | awk '{if (NR!=1) print $6}' | sudo xargs -I '{}' find '{}' -xdev -nogroup Either remove all files and directories from the system that do not have a valid group, or assign a valid group with the chgrp command: $ sudo chgrp group file Is it the case that there is output? If any files are not owned by a group, then the cause of their lack of group-ownership should be investigated. Following this, the files should be deleted or assigned to an appropriate group. The following command will discover and print any files on local partitions which do not belong to a valid group:
$ df --local -P | awk '{if (NR!=1) print $6}' | sudo xargs -I '{}' find '{}' -xdev -nogroup
To search all filesystems on a system including network mounted filesystems the following command can be run manually for each partition:
$ sudo find PARTITION -xdev -nogroup
RHEL-08-010790 file_permissions_ungroupowned
V-230328 366 medium A separate RHEL 8 filesystem must be used for user home directories (such as /home or an equivalent). Ensuring that /home is mounted on its own partition enables the setting of more restrictive mount options, and also helps ensure that users cannot trivially fill partitions used for log or audit data storage. Run the following command to determine if /home is on its own partition or logical volume: $ mount | grep "on /home" If /home has its own partition or volume group, a line will be returned. Is it the case that no line is returned? If user home directories will be stored locally, create a separate partition for /home at installation time (or migrate it later using LVM). If /home will be mounted from another system such as an NFS server, then creating a separate partition is not necessary at installation time, and the mountpoint can instead be configured later. RHEL-08-010800 partition_for_home
V-230329 366 high Unattended or automatic logon via the RHEL 8 graphical user interface must not be allowed. Failure to restrict system access to authenticated users negatively impacts operating system security. To verify that automatic logins are disabled, run the following command: $ grep -Pzoi "^\[daemon]\\nautomaticlogin.*" /etc/gdm/custom.conf The output should show the following: [daemon] AutomaticLoginEnable=false Is it the case that GDM allows users to automatically login? The GNOME Display Manager (GDM) can allow users to automatically login without user interaction or credentials. User should always be required to authenticate themselves to the system that they are authorized to use. To disable user ability to automatically login to the system, set the AutomaticLoginEnable to false in the [daemon] section in /etc/gdm/custom.conf. For example:
[daemon]
AutomaticLoginEnable=false
RHEL-08-010820 gnome_gdm_disable_automatic_login
V-230330 366 medium RHEL 8 must not allow users to override SSH environment variables. SSH environment options potentially allow users to bypass access restriction in some configurations. To ensure users are not able to send environment variables, run the following command: $ sudo grep PermitUserEnvironment /etc/ssh/sshd_config If properly configured, output should be: PermitUserEnvironment no Is it the case that PermitUserEnvironment is not disabled? To ensure users are not able to override environment variables of the SSH daemon, add or correct the following line in /etc/ssh/sshd_config:
PermitUserEnvironment no
RHEL-08-010830 sshd_do_not_permit_user_env
V-230331 16 medium RHEL 8 temporary user accounts must be provisioned with an expiration time of 72 hours or less. If temporary user accounts remain active when no longer needed or for an excessive period, these accounts may be used to gain unauthorized access. To mitigate this risk, automated termination of all temporary accounts must be set upon account creation.
For every temporary and emergency account, run the following command to obtain its account aging and expiration information: $ sudo chage -l USER Verify each of these accounts has an expiration date set as documented. Is it the case that any temporary or emergency accounts have no expiration date set or do not expire within a documented time frame? Temporary accounts are established as part of normal account activation procedures when there is a need for short-term accounts. In the event temporary or emergency accounts are required, configure the system to terminate them after a documented time period. For every temporary and emergency account, run the following command to set an expiration date on it, substituting USER and YYYY-MM-DD appropriately:
$ sudo chage -E YYYY-MM-DD USER
YYYY-MM-DD indicates the documented expiration date for the account. For U.S. Government systems, the operating system must be configured to automatically terminate these types of accounts after a period of 72 hours.
RHEL-08-020000 account_temp_expire_date
V-230332 44 medium RHEL 8 must automatically lock an account when three unsuccessful logon attempts occur. Locking out user accounts after a number of incorrect attempts prevents direct password guessing attacks. To ensure the failed password attempt policy is configured correctly, run the following command: $ grep pam_faillock /etc/pam.d/system-auth The output should show deny=. Is it the case that that is not the case? To configure the system to lock out accounts after a number of incorrect login attempts using pam_faillock.so, modify the content of both /etc/pam.d/system-auth and /etc/pam.d/password-auth as follows:

  • add the following line immediately before the pam_unix.so statement in the AUTH section:
    auth required pam_faillock.so preauth silent deny= unlock_time= fail_interval=
  • add the following line immediately after the pam_unix.so statement in the AUTH section:
    auth [default=die] pam_faillock.so authfail deny= unlock_time= fail_interval=
  • add the following line immediately before the pam_unix.so statement in the ACCOUNT section:
    account required pam_faillock.so
RHEL-08-020010 accounts_passwords_pam_faillock_deny
V-230333 medium RHEL 8 must automatically lock an account when three unsuccessful logon attempts occur. RHEL-08-020011 Missing Rule
V-230334 44 medium RHEL 8 must automatically lock an account when three unsuccessful logon attempts occur during a 15-minute time period. By limiting the number of failed logon attempts the risk of unauthorized system access via user password guessing, otherwise known as brute-forcing, is reduced. Limits are imposed by locking the account. To ensure the failed password attempt policy is configured correctly, run the following command: $ grep pam_faillock /etc/pam.d/system-auth /etc/pam.d/password-auth For each file, the output should show fail_interval=<interval-in-seconds> where interval-in-seconds is or greater. If the fail_interval parameter is not set, the default setting of 900 seconds is acceptable. Is it the case that fail_interval is less than the required value? Utilizing pam_faillock.so, the fail_interval directive configures the system to lock out an account after a number of incorrect login attempts within a specified time period. Modify the content of both /etc/pam.d/system-auth and /etc/pam.d/password-auth as follows:

  • Add the following line immediately before the pam_unix.so statement in the AUTH section:
    auth required pam_faillock.so preauth silent deny= unlock_time= fail_interval=
  • Add the following line immediately after the pam_unix.so statement in the AUTH section:
    auth [default=die] pam_faillock.so authfail deny= unlock_time= fail_interval=
    
  • Add the following line immediately before the pam_unix.so statement in the ACCOUNT section:
    account required pam_faillock.so
RHEL-08-020012 accounts_passwords_pam_faillock_interval
V-230335 medium RHEL 8 must automatically lock an account when three unsuccessful logon attempts occur during a 15-minute time period. RHEL-08-020013 Missing Rule
V-230336 44 medium RHEL 8 must automatically lock an account until the locked account is released by an administrator when three unsuccessful logon attempts occur during a 15-minute time period. Locking out user accounts after a number of incorrect attempts prevents direct password guessing attacks. Ensuring that an administrator is involved in unlocking locked accounts draws appropriate attention to such situations. To ensure the failed password attempt policy is configured correctly, run the following command: $ grep pam_faillock /etc/pam.d/system-auth The output should show unlock_time=<some-large-number> or 0 for never. Is it the case that unlock_time is less than the expected value? To configure the system to lock out accounts after a number of incorrect login attempts and require an administrator to unlock the account using pam_faillock.so, modify the content of both /etc/pam.d/system-auth and /etc/pam.d/password-auth as follows:

  • add the following line immediately before the pam_unix.so statement in the AUTH section:
    auth required pam_faillock.so preauth silent deny= unlock_time= fail_interval=
  • add the following line immediately after the pam_unix.so statement in the AUTH section:
    auth [default=die] pam_faillock.so authfail deny= unlock_time= fail_interval=
  • add the following line immediately before the pam_unix.so statement in the ACCOUNT section:
    account required pam_faillock.so
If unlock_time is set to 0, manual intervention by an administrator is required to unlock a user.
RHEL-08-020014 accounts_passwords_pam_faillock_unlock_time
V-230337 medium RHEL 8 must automatically lock an account until the locked account is released by an administrator when three unsuccessful logon attempts occur during a 15-minute time period. RHEL-08-020015 Missing Rule
V-230338 medium RHEL 8 must ensure account lockouts persist. RHEL-08-020016 Missing Rule
V-230339 medium RHEL 8 must ensure account lockouts persist. RHEL-08-020017 Missing Rule
V-230340 medium RHEL 8 must prevent system messages from being presented when three unsuccessful logon attempts occur. RHEL-08-020018 Missing Rule
V-230341 medium RHEL 8 must prevent system messages from being presented when three unsuccessful logon attempts occur. RHEL-08-020019 Missing Rule
V-230342 medium RHEL 8 must log user name information when unsuccessful logon attempts occur. RHEL-08-020020 Missing Rule
V-230343 medium RHEL 8 must log user name information when unsuccessful logon attempts occur. RHEL-08-020021 Missing Rule
V-230344 44 medium RHEL 8 must include root when automatically locking an account until the locked account is released by an administrator when three unsuccessful logon attempts occur during a 15-minute time period. By limiting the number of failed logon attempts, the risk of unauthorized system access via user password guessing, otherwise known as brute-forcing, is reduced. Limits are imposed by locking the account. To ensure that even the root account is locked after a defined number of failed password attempts, run the following command: $ grep even_deny_root /etc/pam.d/system-auth The output should show even_deny_root. Is it the case that that is not the case? To configure the system to lock out the root account after a number of incorrect login attempts using pam_faillock.so, modify the content of both /etc/pam.d/system-auth and /etc/pam.d/password-auth as follows:

  • Modify the following line in the AUTH section to add even_deny_root:
    auth required pam_faillock.so preauth silent even_deny_root deny= unlock_time= fail_interval=
  • Modify the following line in the AUTH section to add even_deny_root:
    auth [default=die] pam_faillock.so authfail even_deny_root deny= unlock_time= fail_interval=
RHEL-08-020022 accounts_passwords_pam_faillock_deny_root
V-230345 medium RHEL 8 must include root when automatically locking an account until the locked account is released by an administrator when three unsuccessful logon attempts occur during a 15-minute time period. RHEL-08-020023 Missing Rule
V-230346 54 low RHEL 8 must limit the number of concurrent sessions to ten for all accounts and/or account types. Limiting simultaneous user logins can insulate the system from denial of service problems caused by excessive logins. Automated login processes operating improperly or maliciously may result in an exceptional number of simultaneous login sessions. Run the following command to ensure the maxlogins value is configured for all users on the system: # grep "maxlogins" /etc/security/limits.conf You should receive output similar to the following: *\t\thard\tmaxlogins\t Is it the case that maxlogins is not equal to or less than the expected value? Limiting the number of allowed users and sessions per user can limit risks related to Denial of Service attacks. This addresses concurrent sessions for a single account and does not address concurrent sessions by a single user via multiple accounts. To set the number of concurrent sessions per user add the following line in /etc/security/limits.conf or a file under /etc/security/limits.d/:
* hard maxlogins 
RHEL-08-020024 accounts_max_concurrent_login_sessions
V-244533 medium RHEL 8 must configure the use of the pam_faillock.so module in the /etc/pam.d/system-auth file. RHEL-08-020025 Missing Rule
V-244534 medium RHEL 8 must configure the use of the pam_faillock.so module in the /etc/pam.d/password-auth file. RHEL-08-020026 Missing Rule
V-230347 56 medium RHEL 8 must enable a user session lock until that user re-establishes access using established identification and authentication procedures for graphical user sessions. A session lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not want to logout because of the temporary nature of the absense. To check the status of the idle screen lock activation, run the following command: $ gsettings get org.gnome.desktop.screensaver lock-enabled If properly configured, the output should be true. To ensure that users cannot change how long until the the screensaver locks, run the following: $ grep lock-enabled /etc/dconf/db/local.d/locks/* If properly configured, the output for lock-enabled should be /org/gnome/desktop/screensaver/lock-enabled Is it the case that screensaver locking is not enabled and/or has not been set or configured correctly? To activate locking of the screensaver in the GNOME3 desktop when it is activated, add or set lock-enabled to true in /etc/dconf/db/local.d/00-security-settings. For example:
[org/gnome/desktop/screensaver]
lock-enabled=true
Once the settings have been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/desktop/screensaver/lock-enabled
After the settings have been set, run dconf update.
RHEL-08-020030 dconf_gnome_screensaver_lock_enabled
V-244535 medium RHEL 8 must initiate a session lock for graphical user interfaces when the screensaver is activated. RHEL-08-020031 Missing Rule
V-244536 medium RHEL 8 must disable the user list at logon for graphical user interfaces. RHEL-08-020032 Missing Rule
V-244537 56 medium RHEL 8 must have the tmux package installed. A session time-out lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not logout because of the temporary nature of the absence. Rather than relying on the user to manually lock their operation system session prior to vacating the vicinity, operating systems need to be able to identify when a user's session has idled and take action to initiate the session lock.

The tmux package allows for a session lock to be implemented and configured.
Run the following command to determine if the tmux package is installed: $ rpm -q tmux Is it the case that the package is not installed? To enable console screen locking, install the tmux package. The tmux package can be installed with the following command:
$ sudo yum install tmux
Instruct users to begin new terminal sessions with the following command:
$ tmux
The console can now be locked with the following key combination:
ctrl+b :lock-session
RHEL-08-020039 package_tmux_installed
V-230348 56 medium RHEL 8 must enable a user session lock until that user re-establishes access using established identification and authentication procedures for command line sessions. The tmux package allows for a session lock to be implemented and configured. However, the session lock is implemented by an external command. The tmux default configuration does not contain an effective session lock. To verify that vlock is configured as a locking mechanism in tmux, run the following command: $ grep lock-command /etc/tmux.conf The output should return the following: set -g lock-command vlock Is it the case that lock-command is not set? To enable console screen locking in tmux terminal multiplexer, the vlock command must be configured to be used as a locking mechanism. Add the following line to /etc/tmux.conf:
set -g lock-command vlock
. The console can now be locked with the following key combination:
ctrl+b :lock-session
RHEL-08-020040 configure_tmux_lock_command
V-230349 56 medium RHEL 8 must ensure session control is automatically started at shell initialization. Unlike bash itself, the tmux terminal multiplexer provides a mechanism to lock sessions after period of inactivity. To verify that tmux is configured to execute, run the following command: $ grep -A1 -B3 "case ..name. in sshd|login) exec tmux ;; esac" /etc/bashrc The output should return the following: if [ "$PS1" ]; then parent=$(ps -o ppid= -p $$) name=$(ps -o comm= -p $parent) case "$name" in sshd|login) exec tmux ;; esac fi Is it the case that exec tmux is not present at the end of bashrc? The tmux terminal multiplexer is used to implement automatic session locking. It should be started from /etc/bashrc. RHEL-08-020041 configure_bashrc_exec_tmux
V-230350 56 low RHEL 8 must prevent users from disabling session control mechanisms. Not listing tmux among permitted shells prevents malicious program running as user from lowering security by disabling the screen lock. To verify that tmux is not listed as allowed shell on the system run the following command: $ grep 'tmux$' /etc/shells The output should be empty. Is it the case that tmux is listed in /etc/shells? The tmux terminal multiplexer is used to implement automatic session locking. It should not be listed in /etc/shells. RHEL-08-020042 no_tmux_in_shells
V-230351 56 medium RHEL 8 must be able to initiate directly a session lock for all connection types using smartcard when the smartcard is removed. Locking the screen automatically when removing the smartcard can prevent undesired access to system. To ensure screen locking on smartcard removal is enabled, run the following command: $ grep removal-action /etc/dconf/db/local.d/* The output should be 'lock-screen'. To ensure that users cannot disable screen locking on smartcard removal, run the following: $ grep removal-action /etc/dconf/db/local.d/locks/* If properly configured, the output should be /org/gnome/settings-daemon/peripherals/smartcard/removal-action Is it the case that removal-action has not been configured? In the default graphical environment, screen locking on smartcard removal can be enabled by setting removal-action to 'lock-screen'.

To enable, add or edit removal-action to /etc/dconf/db/local.d/00-security-settings. For example:
[org/gnome/settings-daemon/peripherals/smartcard]
removal-action='lock-screen'
Once the setting has been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/settings-daemon/peripherals/smartcard/removal-action
After the settings have been set, run dconf update.
RHEL-08-020050 dconf_gnome_lock_screen_on_smartcard_removal
V-230352 57 medium RHEL 8 must automatically lock graphical user sessions after 15 minutes of inactivity. A session time-out lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not logout because of the temporary nature of the absence. Rather than relying on the user to manually lock their operating system session prior to vacating the vicinity, GNOME3 can be configured to identify when a user's session has idled and take action to initiate a session lock. To check the current idle time-out value, run the following command: $ gsettings get org.gnome.desktop.session idle-delay If properly configured, the output should be 'uint32 '. To ensure that users cannot change the screensaver inactivity timeout setting, run the following: $ grep idle-delay /etc/dconf/db/local.d/locks/* If properly configured, the output should be /org/gnome/desktop/session/idle-delay Is it the case that idle-delay is not equal to or less than the expected value? The idle time-out value for inactivity in the GNOME3 desktop is configured via the idle-delay setting must be set under an appropriate configuration file(s) in the /etc/dconf/db/local.d directory and locked in /etc/dconf/db/local.d/locks directory to prevent user modification.

For example, to configure the system for a 15 minute delay, add the following to /etc/dconf/db/local.d/00-security-settings:
[org/gnome/desktop/session]
idle-delay=uint32 900
Once the setting has been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/desktop/session/idle-delay
After the settings have been set, run dconf update.
RHEL-08-020060 dconf_gnome_screensaver_idle_delay
V-230353 57 medium RHEL 8 must automatically lock command line user sessions after 15 minutes of inactivity. Locking the session after a period of inactivity limits the potential exposure if the session is left unattended. To verify that session locking after period of inactivity is configured in tmux, run the following command: $ grep lock-after-time /etc/tmux.conf The output should return the following: set -g lock-after-time 900 Is it the case that lock-after-time is not set or set to zero? To enable console screen locking in tmux terminal multiplexer after a period of inactivity, the lock-after-time option has to be set to nonzero value in /etc/tmux.conf. RHEL-08-020070 configure_tmux_lock_after_time
V-230354 medium RHEL 8 must prevent a user from overriding the session lock-delay setting for the graphical user interface. RHEL-08-020080 Missing Rule
V-244538 medium RHEL 8 must prevent a user from overriding the session idle-delay setting for the graphical user interface. RHEL-08-020081 Missing Rule
V-244539 medium RHEL 8 must prevent a user from overriding the screensaver lock-enabled setting for the graphical user interface. RHEL-08-020082 Missing Rule
V-230355 187 medium RHEL 8 must map the authenticated identity to the user or group account for PKI-based authentication. Without mapping the certificate used to authenticate to the user account, the ability to determine the identity of the individual user or group will not be available for forensic analysis. To verify Certmap is enabled in SSSD, run the following command: $ cat sudo cat /etc/sssd/sssd.conf If configured properly, output should contain section like the following [certmap/testing.test/rule_name] matchrule =<SAN>.*EDIPI@mil maprule = (userCertificate;binary={cert!bin}) domains = testing.test Is it the case that Certmap is not configured in SSSD? SSSD should be configured to verify the certificate of the user or group. To set this up ensure that section like certmap/testing.test/rule_name is setup in /etc/sssd/sssd.conf. For example
[certmap/testing.test/rule_name]
matchrule =<SAN>.*EDIPI@mil
maprule = (userCertificate;binary={cert!bin})
domains = testing.test
RHEL-08-020090 sssd_enable_certmap
V-230356 192 medium RHEL 8 must ensure a password complexity module is enabled. Setting the password retry prompts that are permitted on a per-session basis to a low value requires some software, such as SSH, to re-connect. This can slow down and draw additional attention to some types of password-guessing attacks. Note that this is different from account lockout, which is provided by the pam_faillock module. To check how many retry attempts are permitted on a per-session basis, run the following command: $ grep pam_pwquality /etc/pam.d/system-auth The retry parameter will indicate how many attempts are permitted. The DoD required value is less than or equal to 3. This would appear as retry=3, or a lower value. Is it the case that it is not the required value? To configure the number of retry prompts that are permitted per-session: Edit the pam_pwquality.so statement in /etc/pam.d/system-auth to show retry=, or a lower value if site policy is more restrictive. The DoD requirement is a maximum of 3 prompts per session. RHEL-08-020100 accounts_password_pam_retry
V-230357 192 medium RHEL 8 must enforce password complexity by requiring that at least one uppercase character be used. Use of a complex password helps to increase the time and resources reuiqred to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks.

Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possible combinations that need to be tested before the password is compromised.
To check how many uppercase characters are required in a password, run the following command: $ grep ucredit /etc/security/pwquality.conf The ucredit parameter (as a negative number) will indicate how many uppercase characters are required. The DoD and FISMA require at least one uppercase character in a password. This would appear as ucredit = -1. Is it the case that ucredit is not found or not set less than or equal to the required value? The pam_pwquality module's ucredit= parameter controls requirements for usage of uppercase letters in a password. When set to a negative number, any password will be required to contain that many uppercase characters. When set to a positive number, pam_pwquality will grant +1 additional length credit for each uppercase character. Modify the ucredit setting in /etc/security/pwquality.conf to require the use of an uppercase character in passwords. RHEL-08-020110 accounts_password_pam_ucredit
V-230358 193 medium RHEL 8 must enforce password complexity by requiring that at least one lower-case character be used. Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks.

Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possble combinations that need to be tested before the password is compromised. Requiring a minimum number of lowercase characters makes password guessing attacks more difficult by ensuring a larger search space.
To check how many lowercase characters are required in a password, run the following command: $ grep lcredit /etc/security/pwquality.conf The lcredit parameter (as a negative number) will indicate how many special characters are required. The DoD and FISMA require at least one lowercase character in a password. This would appear as lcredit = -1. Is it the case that lcredit is not found or not less than or equal to the required value? The pam_pwquality module's lcredit parameter controls requirements for usage of lowercase letters in a password. When set to a negative number, any password will be required to contain that many lowercase characters. When set to a positive number, pam_pwquality will grant +1 additional length credit for each lowercase character. Modify the lcredit setting in /etc/security/pwquality.conf to require the use of a lowercase character in passwords. RHEL-08-020120 accounts_password_pam_lcredit
V-230359 194 medium RHEL 8 must enforce password complexity by requiring that at least one numeric character be used. Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks.

Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possible combinations that need to be tested before the password is compromised. Requiring digits makes password guessing attacks more difficult by ensuring a larger search space.
To check how many digits are required in a password, run the following command: $ grep dcredit /etc/security/pwquality.conf The dcredit parameter (as a negative number) will indicate how many digits are required. The DoD requires at least one digit in a password. This would appear as dcredit = -1. Is it the case that dcredit is not found or not equal to or less than the required value? The pam_pwquality module's dcredit parameter controls requirements for usage of digits in a password. When set to a negative number, any password will be required to contain that many digits. When set to a positive number, pam_pwquality will grant +1 additional length credit for each digit. Modify the dcredit setting in /etc/security/pwquality.conf to require the use of a digit in passwords. RHEL-08-020130 accounts_password_pam_dcredit
V-230360 195 medium RHEL 8 must require the maximum number of repeating characters of the same character class be limited to four when passwords are changed. Use of a complex password helps to increase the time and resources required to comrpomise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks.
Password complexity is one factor of several that determines how long it takes to crack a password. The more complex a password, the greater the number of possible combinations that need to be tested before the password is compromised.
To check the value for maximum consecutive repeating characters, run the following command: $ grep maxclassrepeat /etc/security/pwquality.conf For DoD systems, the output should show maxclassrepeat=4. Is it the case that that is not the case? The pam_pwquality module's maxclassrepeat parameter controls requirements for consecutive repeating characters from the same character class. When set to a positive number, it will reject passwords which contain more than that number of consecutive characters from the same character class. Modify the maxclassrepeat setting in /etc/security/pwquality.conf to equal to prevent a run of ( + 1) or more identical characters. RHEL-08-020140 accounts_password_pam_maxclassrepeat
V-230361 195 medium RHEL 8 must require the maximum number of repeating characters be limited to three when passwords are changed. Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks.

Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possible combinations that need to be tested before the password is compromised.

Passwords with excessive repeating characters may be more vulnerable to password-guessing attacks.
To check the maximum value for consecutive repeating characters, run the following command: $ grep maxrepeat /etc/security/pwquality.conf Look for the value of the maxrepeat parameter. The DoD requirement is 3, which would appear as maxrepeat=3. Is it the case that maxrepeat is not found or not greater than or equal to the required value? The pam_pwquality module's maxrepeat parameter controls requirements for consecutive repeating characters. When set to a positive number, it will reject passwords which contain more than that number of consecutive characters. Modify the maxrepeat setting in /etc/security/pwquality.conf to equal to prevent a run of ( + 1) or more identical characters. RHEL-08-020150 accounts_password_pam_maxrepeat
V-230362 195 medium RHEL 8 must require the change of at least four character classes when passwords are changed. Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks.

Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possible combinations that need to be tested before the password is compromised.

Requiring a minimum number of character categories makes password guessing attacks more difficult by ensuring a larger search space.
To check how many categories of characters must be used in password during a password change, run the following command: $ grep minclass /etc/security/pwquality.conf The minclass parameter will indicate how many character classes must be used. If the requirement was for the password to contain characters from three different categories, then this would appear as minclass = 3. Is it the case that minclass is not found or not set equal to or greater than the required value? The pam_pwquality module's minclass parameter controls requirements for usage of different character classes, or types, of character that must exist in a password before it is considered valid. For example, setting this value to three (3) requires that any password must have characters from at least three different categories in order to be approved. The default value is zero (0), meaning there are no required classes. There are four categories available:
* Upper-case characters
* Lower-case characters
* Digits
* Special characters (for example, punctuation)
Modify the minclass setting in /etc/security/pwquality.conf entry to require differing categories of characters when changing passwords.
RHEL-08-020160 accounts_password_pam_minclass
V-230363 195 medium RHEL 8 must require the change of at least 8 characters when passwords are changed. Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute–force attacks.

Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possible combinations that need to be tested before the password is compromised.

Requiring a minimum number of different characters during password changes ensures that newly changed passwords should not resemble previously compromised ones. Note that passwords which are changed on compromised systems will still be compromised, however.
To check how many characters must differ during a password change, run the following command: $ grep difok /etc/security/pwquality.conf The difok parameter will indicate how many characters must differ. Is it the case that difok is not found or not equal to or greater than the required value? The pam_pwquality module's difok parameter sets the number of characters in a password that must not be present in and old password during a password change.

Modify the difok setting in /etc/security/pwquality.conf to equal to require differing characters when changing passwords.
RHEL-08-020170 accounts_password_pam_difok
V-230364 198 medium RHEL 8 passwords must have a 24 hours/1 day minimum password lifetime restriction in /etc/shadow. Enforcing a minimum password lifetime helps to prevent repeated password changes to defeat the password reuse or history enforcement requirement. If users are allowed to immediately and continually change their password, the password could be repeatedly changed in a short period of time to defeat the organization's policy regarding password reuse. Check whether the minimum time period between password changes for each user account is one day or greater by running the following command for each user: $ sudo chage -l USER | grep Minimum The output for each user should return something similary to the following: Minimum number of days between password change\t\t: 1 Is it the case that existing passwords are not configured correctly? Configure non-compliant accounts to enforce a 24 hours/1 day minimum password lifetime by running the following command:
$ sudo chage -m 1 USER
RHEL-08-020180 accounts_password_set_min_life_existing
V-230365 198 medium RHEL 8 passwords for new users or password changes must have a 24 hours/1 day minimum password lifetime restriction in /etc/logins.def. Enforcing a minimum password lifetime helps to prevent repeated password changes to defeat the password reuse or history enforcement requirement. If users are allowed to immediately and continually change their password, then the password could be repeatedly changed in a short period of time to defeat the organization's policy regarding password reuse.

Setting the minimum password age protects against users cycling back to a favorite password after satisfying the password reuse requirement.
To check the minimum password age, run the command: $ grep PASS_MIN_DAYS /etc/login.defs Is it the case that it is not equal to or greater than the required value? To specify password minimum age for new accounts, edit the file /etc/login.defs and add or correct the following line:
PASS_MIN_DAYS 
A value of 1 day is considered sufficient for many environments. The DoD requirement is 1. The profile requirement is .
RHEL-08-020190 accounts_minimum_age_login_defs
V-230366 199 medium RHEL 8 user account passwords must have a 60-day maximum password lifetime restriction. Any password, no matter how complex, can eventually be cracked. Therefore, passwords need to be changed periodically. If the operating system does not limit the lifetime of passwords and force users to change their passwords, there is the risk that the operating system passwords could be compromised.

Setting the password maximum age ensures users are required to periodically change their passwords. Requiring shorter password lifetimes increases the risk of users writing down the password in a convenient location subject to physical compromise.
To check the maximum password age, run the command: $ grep PASS_MAX_DAYS /etc/login.defs The DoD and FISMA requirement is 60. A value of 180 days is sufficient for many environments. Is it the case that PASS_MAX_DAYS is not set equal to or greater than the required value? To specify password maximum age for new accounts, edit the file /etc/login.defs and add or correct the following line:
PASS_MAX_DAYS 
A value of 180 days is sufficient for many environments. The DoD requirement is 60. The profile requirement is .
RHEL-08-020200 accounts_maximum_age_login_defs
V-230367 199 medium RHEL 8 user account passwords must be configured so that existing passwords are restricted to a 60-day maximum lifetime. Any password, no matter how complex, can eventually be cracked. Therefore, passwords need to be changed periodically. If the operating system does not limit the lifetime of passwords and force users to change their passwords, there is the risk that the operating system passwords could be compromised. Check whether the maximum time period for existing passwords is restricted to 60 days by running the following command for each user: $ sudo chage -l USER | grep Maximum The output for each user should return something similary to the following: Maximum number of days between password change\t\t: 60 Is it the case that existing passwords are not configured correctly? Configure non-compliant accounts to enforce a 60-day maximum password lifetime restriction by running the following command:
$ sudo chage -M 60 USER
RHEL-08-020210 accounts_password_set_max_life_existing
V-230368 200 medium RHEL 8 passwords must be prohibited from reuse for a minimum of five generations. Preventing re-use of previous passwords helps ensure that a compromised password is not re-used by a user. Check that the operating system prohibits the reuse of a password for a minimum of generations with the following command: # grep pam_pwhistory.so /etc/pam.d/system-auth password pam_pwhistory.so remember= use_authtok If the command does not return a result, or the returned line is commented out, has a second column value different from , does not contain "remember" value, or the value is less than , this is a finding. Is it the case that the value of remember is not set equal to or greater than <sub idref="var_password_pam_remember" />? Do not allow users to reuse recent passwords. This can be accomplished by using the remember option for the pam_pwhistory PAM modules.

In the file /etc/pam.d/system-auth, make sure the parameter remember is present, and that the value for the remember parameter is or greater. For example:
password  pam_pwhistory.so ...existing_options... remember= use_authtok
The DoD STIG requirement is 5 passwords.
RHEL-08-020220 accounts_password_pam_pwhistory_remember_system_auth
V-230369 205 medium RHEL 8 passwords must have a minimum of 15 characters. The shorter the password, the lower the number of possible combinations that need to be tested before the password is compromised.
Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. Password length is one factor of several that helps to determine strength and how long it takes to crack a password. Use of more characters in a password helps to exponentially increase the time and/or resources required to compromose the password.
To check how many characters are required in a password, run the following command: $ grep minlen /etc/security/pwquality.conf Your output should contain minlen = Is it the case that minlen is not found, or not equal to or greater than the required value? The pam_pwquality module's minlen parameter controls requirements for minimum characters required in a password. Add minlen= after pam_pwquality to set minimum password length requirements. RHEL-08-020230 accounts_password_pam_minlen
V-230370 205 medium RHEL 8 passwords for new users must have a minimum of 15 characters. Requiring a minimum password length makes password cracking attacks more difficult by ensuring a larger search space. However, any security benefit from an onerous requirement must be carefully weighed against usability problems, support costs, or counterproductive behavior that may result. To check the minimum password length, run the command: $ grep PASS_MIN_LEN /etc/login.defs The DoD requirement is 15. Is it the case that it is not set to the required value? To specify password length requirements for new accounts, edit the file /etc/login.defs and add or correct the following line:
PASS_MIN_LEN 


The DoD requirement is 15. The FISMA requirement is 12. The profile requirement is . If a program consults /etc/login.defs and also another PAM module (such as pam_pwquality) during a password change operation, then the most restrictive must be satisfied. See PAM section for more information about enforcing password quality requirements.
RHEL-08-020231 accounts_password_minlen_login_defs
V-230371 764 medium RHEL 8 duplicate User IDs (UIDs) must not exist for interactive users. To assure accountability and prevent unauthenticated access, interactive users must be identified and authenticated to prevent potential misuse and compromise of the system. Run the following command to check for duplicate account names: Check that the operating system contains no duplicate UIDs for interactive users by running the following command: # awk -F ":" 'list[$3]++{print $1, $3}' /etc/passwd If output is produced, this is a finding. Configure the operating system to contain no duplicate UIDs for interactive users. Edit the file "/etc/passwd" and provide each interactive user account that has a duplicate UID with a unique UID. Is it the case that a line is returned? Change user IDs (UIDs), or delete accounts, so each has a unique name. RHEL-08-020240 account_unique_id
V-230372 765 medium RHEL 8 must implement smart card logon for multifactor authentication for access to interactive accounts. Using an authentication device, such as a CAC or token that is separate from the information system, ensures that even if the information system is compromised, that compromise will not affect credentials stored on the authentication device.

Multifactor solutions that require devices separate from information systems gaining access include, for example, hardware tokens providing time-based or challenge-response authenticators and smart cards such as the U.S. Government Personal Identity Verification card and the DoD Common Access Card.
To verify that smart cards are enabled in SSSD, run the following command: $ sudo grep pam_cert_auth /etc/sssd/sssd.conf If configured properly, output should be pam_cert_auth = true Is it the case that smart cards are not enabled in SSSD? SSSD should be configured to authenticate access to the system using smart cards. To enable smart cards in SSSD, set pam_cert_auth to true under the [pam] section in /etc/sssd/sssd.conf. For example:
[pam]
pam_cert_auth = true
RHEL-08-020250 sssd_enable_smartcards
V-230373 795 medium RHEL 8 account identifiers (individuals, groups, roles, and devices) must be disabled after 35 days of inactivity. Disabling inactive accounts ensures that accounts which may not have been responsibly removed are not available to attackers who may have compromised their credentials. To verify the INACTIVE setting, run the following command: $ grep "INACTIVE" /etc/default/useradd The output should indicate the INACTIVE configuration option is set to an appropriate integer as shown in the example below: $ grep "INACTIVE" /etc/default/useradd INACTIVE= Is it the case that the value of INACTIVE is greater than the expected value? To specify the number of days after a password expires (which signifies inactivity) until an account is permanently disabled, add or correct the following line in /etc/default/useradd:
INACTIVE=
If a password is currently on the verge of expiration, then day(s) remain(s) until the account is automatically disabled. However, if the password will not expire for another 60 days, then 60 days plus day(s) could elapse until the account would be automatically disabled. See the useradd man page for more information.
RHEL-08-020260 account_disable_post_pw_expiration
V-230374 1682 medium RHEL 8 emergency accounts must be automatically removed or disabled after the crisis is resolved or within 72 hours. If emergency user accounts remain active when no longer needed or for an excessive period, these accounts may be used to gain unauthorized access. To mitigate this risk, automated termination of all emergency accounts must be set upon account creation.
For every emergency account, run the following command to obtain its account aging and expiration information: $ sudo chage -l ACCOUNT_NAME Verify each of these accounts has an expiration date set as documented. Is it the case that any emergency accounts have no expiration date set or do not expire within a documented time frame? Emergency accounts are privileged accounts established in response to crisis situations where the need for rapid account activation is required. In the event emergency accounts are required, configure the system to terminate them after a documented time period. For every emergency account, run the following command to set an expiration date on it, substituting ACCOUNT_NAME and YYYY-MM-DD appropriately:
$ sudo chage -E YYYY-MM-DD ACCOUNT_NAME
YYYY-MM-DD indicates the documented expiration date for the account. For U.S. Government systems, the operating system must be configured to automatically terminate these types of accounts after a period of 72 hours.
RHEL-08-020270 account_emergency_expire_date
V-230375 1619 medium All RHEL 8 passwords must contain at least one special character. Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks.

Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possble combinations that need to be tested before the password is compromised. Requiring a minimum number of special characters makes password guessing attacks more difficult by ensuring a larger search space.
To check how many special characters are required in a password, run the following command: $ grep ocredit /etc/security/pwquality.conf The ocredit parameter (as a negative number) will indicate how many special characters are required. The DoD and FISMA require at least one special character in a password. This would appear as ocredit = -1. Is it the case that ocredit is not found or not equal to or less than the required value? The pam_pwquality module's ocredit= parameter controls requirements for usage of special (or "other") characters in a password. When set to a negative number, any password will be required to contain that many special characters. When set to a positive number, pam_pwquality will grant +1 additional length credit for each special character. Modify the ocredit setting in /etc/security/pwquality.conf to equal to require use of a special character in passwords. RHEL-08-020280 accounts_password_pam_ocredit
V-230376 2007 medium RHEL 8 must prohibit the use of cached authentications after one day. If cached authentication information is out-of-date, the validity of the authentication information may be questionable. To verify that SSSD expires offline credentials, run the following command: $ sudo grep offline_credentials_expiration /etc/sssd/sssd.conf If configured properly, output should be offline_credentials_expiration = 1 Is it the case that it does not exist or is not configured properly? SSSD should be configured to expire offline credentials after 1 day. To configure SSSD to expire offline credentials, set offline_credentials_expiration to 1 under the [pam] section in /etc/sssd/sssd.conf. For example:
[pam]
offline_credentials_expiration = 1
RHEL-08-020290 sssd_offline_cred_expiration
V-230377 366 medium RHEL 8 must prevent the use of dictionary words for passwords. Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks.

Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possible combinations that need to be tested before the password is compromised.

Passwords with dictionary words may be more vulnerable to password-guessing attacks.
To check if dictionary words are disallowed run the following command: $ sudo grep dictcheck /etc/security/pwquality.conf /etc/pwquality.conf.d/*.conf The dictcheck parameter should be equal to 1. The value should look like dictcheck=1 Is it the case that dictcheck is not found or not equal to the required value? The pam_pwquality module's dictcheck check if passwords contains dictionary words. When dictcheck is set to 1 passwords will be checked for dictionary words. RHEL-08-020300 accounts_password_pam_dictcheck
V-230378 366 medium RHEL 8 must enforce a delay of at least four seconds between logon prompts following a failed logon attempt. Increasing the time between a failed authentication attempt and re-prompting to enter credentials helps to slow a single-threaded brute force attack. Verify the FAIL_DELAY setting is configured correctly in the /etc/login.defs file by running the following command: $ sudo grep -i "FAIL_DELAY" /etc/login.defs All output must show the value of FAIL_DELAY set as shown in the below: $ sudo grep -i "FAIL_DELAY" /etc/login.defs FAIL_DELAY Is it the case that the above command returns no output, or FAIL_DELAY is configured less than the expected value? To ensure the logon failure delay controlled by /etc/login.defs is set properly, add or correct the FAIL_DELAY setting in /etc/login.defs to read as follows:
FAIL_DELAY 
RHEL-08-020310 accounts_logon_fail_delay
V-230379 366 medium RHEL 8 must not have unnecessary accounts. Accounts providing no operational purpose provide additional opportunities for system compromise. Unnecessary accounts include user accounts for individuals not requiring access to the system and application accounts for applications not installed on the system. To verify that there are no unauthorized local user accounts, run the following command: $ less /etc/passwd Inspect the results, and if unauthorized local user accounts exist, remove them by running the following command: $ sudo userdel unauthorized_user Is it the case that there are unauthorized local user accounts on the system? Enterprise Application tends to use the server or virtual machine exclusively. Besides the default operating system user, there should be only authorized local users required by the installed softoware groups and applications that exist on the operating system. The authorized user list can be customized in the refine value variable var_accounts_authorized_local_users_regex. OVAL regular expression is used for the user list. Configure the system so all accounts on the system are assigned to an active system, application, or user account. Remove accounts that do not support approved system activities or that allow for a normal user to perform administrative-level actions. To remove unauthorized system accounts, use the following command:
$ sudo userdel unauthorized_user
RHEL-08-020320 accounts_authorized_local_users
V-230380 366 high RHEL 8 must not allow accounts configured with blank or null passwords. Configuring this setting for the SSH daemon provides additional assurance that remote login via SSH will require a password, even in the event of misconfiguration elsewhere. To determine how the SSH daemon's PermitEmptyPasswords option is set, run the following command: $ sudo grep -i PermitEmptyPasswords /etc/ssh/sshd_config If no line, a commented line, or a line indicating the value no is returned, then the required value is set. Is it the case that the required value is not set? To explicitly disallow SSH login from accounts with empty passwords, add or correct the following line in /etc/ssh/sshd_config:
PermitEmptyPasswords no

Any accounts with empty passwords should be disabled immediately, and PAM configuration should prevent users from being able to assign themselves empty passwords.
RHEL-08-020330 sshd_disable_empty_passwords
V-244540 366 high RHEL 8 must not allow blank or null passwords in the system-auth file. If an account has an empty password, anyone could log in and run commands with the privileges of that account. Accounts with empty passwords should never be used in operational environments. To verify that null passwords cannot be used, run the following command: $ grep nullok /etc/pam.d/system-auth If this produces any output, it may be possible to log into accounts with empty passwords. Remove any instances of the nullok option to prevent logins with empty passwords. Is it the case that NULL passwords can be used? If an account is configured for password authentication but does not have an assigned password, it may be possible to log into the account without authentication. Remove any instances of the nullok in /etc/pam.d/system-auth to prevent logins with empty passwords. Note that this rule is not applicable for systems running within a container. Having user with empty password within a container is not considered a risk, because it should not be possible to directly login into a container anyway. RHEL-08-020331 no_empty_passwords
V-244541 high RHEL 8 must not allow blank or null passwords in the password-auth file. RHEL-08-020332 Missing Rule
V-230381 366 low RHEL 8 must display the date and time of the last successful account logon upon logon. Users need to be aware of activity that occurs regarding their account. Providing users with information regarding the number of unsuccessful attempts that were made to login to their account allows the user to determine if any unauthorized activity has occurred and gives them an opportunity to notify administrators. To ensure that last logon/access notification is configured correctly, run the following command: $ grep pam_lastlog.so /etc/pam.d/postlogin The output should show output showfailed and must not contain silent. Is it the case that that is not the case? To configure the system to notify users of last logon/access using pam_lastlog, add or correct the pam_lastlog settings in /etc/pam.d/postlogin to read as follows:
session     required pam_lastlog.so showfailed
And make sure that the silent option is not set.
RHEL-08-020340 display_login_attempts
V-230382 366 medium RHEL 8 must display the date and time of the last successful account logon upon an SSH logon. Providing users feedback on when account accesses last occurred facilitates user recognition and reporting of unauthorized account use. To check if PrintLastLog is enabled or set correctly, run the following command: $ sudo grep PrintLastLog /etc/ssh/sshd_config If configured properly, output should be yes Is it the case that it is commented out or is not enabled? When enabled, SSH will display the date and time of the last successful account logon. To enable LastLog in SSH, add or correct the following line in the /etc/ssh/sshd_config file:
PrintLastLog yes
RHEL-08-020350 sshd_print_last_log
V-230383 366 medium RHEL 8 must define default permissions for all authenticated users in such a way that the user can only read and modify their own files. The umask value influences the permissions assigned to files when they are created. A misconfigured umask value could result in files with excessive permissions that can be read and written to by unauthorized users. Verify the UMASK setting is configured correctly in the /etc/login.defs file by running the following command: # grep -i "UMASK" /etc/login.defs All output must show the value of umask set as shown in the below: # grep -i "UMASK" /etc/login.defs umask Is it the case that the above command returns no output, or if the umask is configured incorrectly? To ensure the default umask controlled by /etc/login.defs is set properly, add or correct the UMASK setting in /etc/login.defs to read as follows:
UMASK 
RHEL-08-020351 accounts_umask_etc_login_defs
V-230384 366 medium RHEL 8 must set the umask value to 077 for all local interactive user accounts. The umask controls the default access mode assigned to newly created files. A umask of 077 limits new files to mode 700 or less permissive. Although umask can be represented as a four-digit number, the first digit representing special access modes is typically ignored or required to be 0. This requirement applies to the globally configured system defaults and the local interactive user defaults for each account on the system. Verify the UMASK setting is not configured for interactive users, run the following command: $ sudo grep -ri "UMASK" /home There should be no output. Is it the case that the above command returns no output, or if the umask is configured incorrectly? Remove the UMASK environment variable from all interactive users initialization files. RHEL-08-020352 accounts_umask_interactive_users
V-230385 366 medium RHEL 8 must define default permissions for logon and non-logon shells. The umask value influences the permissions assigned to files when they are created. A misconfigured umask value could result in files with excessive permissions that can be read or written to by unauthorized users. Verify the umask setting is configured correctly in the /etc/bashrc file by running the following command: # grep "umask" /etc/bashrc All output must show the value of umask set as shown below: # grep "umask" /etc/bashrc umask umask Is it the case that the above command returns no output, or if the umask is configured incorrectly? To ensure the default umask for users of the Bash shell is set properly, add or correct the umask setting in /etc/bashrc to read as follows:
umask 
RHEL-08-020353 accounts_umask_etc_bashrc
V-230386 2233 medium The RHEL 8 audit system must be configured to audit the execution of privileged functions and prevent all software from executing at higher privilege levels than users executing the software. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised information system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider threats and the advanced persistent threat. Add or update the following rules in "/etc/audit/rules.d/audit.rules": -a always,exit -F arch=b32 -S execve -C uid!=euid -F euid=0 -k setuid -a always,exit -F arch=b64 -S execve -C uid!=euid -F euid=0 -k setuid -a always,exit -F arch=b32 -S execve -C gid!=egid -F egid=0 -k setgid -a always,exit -F arch=b64 -S execve -C gid!=egid -F egid=0 -k setgid The audit daemon must be restarted for the changes to take effect. # sudo systemctl restart auditd.service Is it the case that it is not the case? Verify the system generates an audit record when privileged functions are executed.
# grep -iw execve /etc/audit/audit.rules
-a always,exit -F arch=b32 -S execve -C uid!=euid -F euid=0 -k setuid
-a always,exit -F arch=b64 -S execve -C uid!=euid -F euid=0 -k setuid
-a always,exit -F arch=b32 -S execve -C gid!=egid -F egid=0 -k setgid
-a always,exit -F arch=b64 -S execve -C gid!=egid -F egid=0 -k setgid
If both the "b32" and "b64" audit rules for "SUID" files are not defined, this is a finding. If both the "b32" and "b64" audit rules for "SGID" files are not defined, this is a finding.
RHEL-08-030000 audit_rules_suid_privilege_function
V-230387 366 medium Cron logging must be implemented in RHEL 8. Cron logging can be used to trace the successful or unsuccessful execution of cron jobs. It can also be used to spot intrusions into the use of the cron facility by unauthorized and malicious users. To verify that cron is logging to rsyslog, run the following command: grep -rni "cron\.\*" /etc/rsyslog.* The output should return some similar to: cron.* /var/log/cron Is it the case that cron is not logging to rsyslog? Cron logging must be implemented to spot intrusions or trace cron job status. If cron is not logging to rsyslog, it can be implemented by adding the following to the RULES section of /etc/rsyslog.conf:
cron.*                                                  /var/log/cron
RHEL-08-030010 rsyslog_cron_logging
V-230388 139 medium The RHEL 8 System Administrator (SA) and Information System Security Officer (ISSO) (at a minimum) must be alerted of an audit processing failure event. Email sent to the root account is typically aliased to the administrators of the system, who can take appropriate action. Inspect /etc/audit/auditd.conf and locate the following line to determine if the system is configured to send email to an account when it needs to notify an administrator: action_mail_acct = Is it the case that auditd is not configured to send emails per identified actions? The auditd service can be configured to send email to a designated account in certain situations. Add or correct the following line in /etc/audit/auditd.conf to ensure that administrators are notified via email for those situations:
action_mail_acct = 
RHEL-08-030020 auditd_data_retention_action_mail_acct
V-230389 139 medium The RHEL 8 Information System Security Officer (ISSO) and System Administrator (SA) (at a minimum) must have mail aliases to be notified of an audit processing failure. A number of system services utilize email messages sent to the root user to notify system administrators of active or impending issues. These messages must be forwarded to at least one monitored email address. Find the list of alias maps used by the Postfix mail server: $ sudo postconf alias_maps Query the Postfix alias maps for an alias for the root user: $ sudo postmap -q root hash:/etc/aliases The output should return an alias. Is it the case that it is not? Make sure that mails delivered to root user are forwarded to a monitored email address. Make sure that the address is a valid email address reachable from the system in question. Use the following command to configure the alias:
$ sudo echo "root: " >> /etc/aliases
$ sudo newaliases
RHEL-08-030030 postfix_client_configure_mail_alias
V-230390 140 medium The RHEL 8 System must take appropriate action when an audit processing failure occurs. Taking appropriate action in case of disk errors will minimize the possibility of losing audit records. Inspect /etc/audit/auditd.conf and locate the following line to determine if the system is configured to either log to syslog, switch to single-user mode, execute a script, or halt when the disk errors: disk_error_action single Is it the case that the system is not configured to switch to single-user mode for corrective action? The auditd service can be configured to take an action when there is a disk error. Edit the file /etc/audit/auditd.conf. Add or modify the following line, substituting ACTION appropriately:
disk_error_action = ACTION
Set this value to single to cause the system to switch to single-user mode for corrective action. Acceptable values also include syslog, exec, single, and halt. For certain systems, the need for availability outweighs the need to log all actions, and a different setting should be determined. Details regarding all possible values for ACTION are described in the auditd.conf man page.
RHEL-08-030040 auditd_data_disk_error_action
V-230391 140 medium The RHEL 8 System Administrator (SA) and Information System Security Officer (ISSO) (at a minimum) must be alerted when the audit storage volume is full. Automatically rotating logs (by setting this to rotate) minimizes the chances of the system unexpectedly running out of disk space by being overwhelmed with log data. However, for systems that must never discard log data, or which use external processes to transfer it and reclaim space, keep_logs can be employed. Inspect /etc/audit/auditd.conf and locate the following line to determine if the system is configured to rotate logs when they reach their maximum size: $ sudo grep max_log_file_action /etc/audit/auditd.conf max_log_file_action rotate Is it the case that the system has not been properly configured to rotate audit logs? The default action to take when the logs reach their maximum size is to rotate the log files, discarding the oldest one. To configure the action taken by auditd, add or correct the line in /etc/audit/auditd.conf:
max_log_file_action = ACTION
Possible values for ACTION are described in the auditd.conf man page. These include:
  • syslog
  • suspend
  • rotate
  • keep_logs
Set the ACTION to rotate to ensure log rotation occurs. This is the default. The setting is case-insensitive.
RHEL-08-030050 auditd_data_retention_max_log_file_action
V-230392 140 medium The RHEL 8 audit system must take appropriate action when the audit storage volume is full. Taking appropriate action in case of a filled audit storage volume will minimize the possibility of losing audit records. Inspect /etc/audit/auditd.conf and locate the following line to determine if the system is configured to either log to syslog, switch to single-user mode, execute a script, or halt when the disk is out of space: disk_full_action single Is it the case that the system is not configured to switch to single-user mode for corrective action? The auditd service can be configured to take an action when disk space is running low but prior to running out of space completely. Edit the file /etc/audit/auditd.conf. Add or modify the following line, substituting ACTION appropriately:
disk_full_action = ACTION
Set this value to single to cause the system to switch to single-user mode for corrective action. Acceptable values also include syslog, exec, single, and halt. For certain systems, the need for availability outweighs the need to log all actions, and a different setting should be determined. Details regarding all possible values for ACTION are described in the auditd.conf man page.
RHEL-08-030060 auditd_data_disk_full_action
V-230393 366 medium The RHEL 8 audit system must audit local events. If option local_events isn't set to yes only events from network will be aggregated. To verify that Audit Daemon is configured to include local events, run the following command: $ sudo grep local_events /etc/audit/auditd.conf The output should return the following: local_events = yes Is it the case that local_events isn't set to yes? To configure Audit daemon to include local events in Audit logs, set local_events to yes in /etc/audit/auditd.conf. This is the default setting. RHEL-08-030061 auditd_local_events
V-230394 1851 medium RHEL 8 must label all off-loaded audit logs before sending them to the central log server. If option name_format is left at its default value of none, audit events from different computers may be hard to distinguish. To verify that Audit Daemon is configured to record the hostname in audit events, run the following command: $ sudo grep name_format /etc/audit/auditd.conf The output should return the following: name_format = hostname Is it the case that name_format isn't set to hostname? To configure Audit daemon to use value returned by gethostname syscall as computer node name in the audit events, set name_format to hostname in /etc/audit/auditd.conf. RHEL-08-030062 auditd_name_format
V-230395 366 low RHEL 8 must resolve audit information before writing to disk. If option log_format isn't set to ENRICHED, the audit records will be stored in a format exactly as the kernel sends them. To verify that Audit Daemon is configured to resolve all uid, gid, syscall, architecture, and socket address information before writing the event to disk, run the following command: $ sudo grep log_format /etc/audit/auditd.conf The output should return the following: log_format = ENRICHED Is it the case that log_format isn't set to ENRICHED? To configure Audit daemon to resolve all uid, gid, syscall, architecture, and socket address information before writing the events to disk, set log_format to ENRICHED in /etc/audit/auditd.conf. RHEL-08-030063 auditd_log_format
V-230396 162 medium RHEL 8 audit logs must have a mode of 0600 or less permissive to prevent unauthorized read access. If users can write to audit logs, audit trails can be modified or destroyed. Run the following command to check the mode of the system audit logs: $ sudo ls -l /var/log/audit Audit logs must be mode 0640 or less permissive. Is it the case that any are more permissive? If log_group in /etc/audit/auditd.conf is set to a group other than the root group account, change the mode of the audit log files with the following command:
$ sudo chmod 0640 audit_file

Otherwise, change the mode of the audit log files with the following command:
$ sudo chmod 0600 audit_file
RHEL-08-030070 file_permissions_var_log_audit
V-230397 162 medium RHEL 8 audit logs must be owned by root to prevent unauthorized read access. Unauthorized disclosure of audit records can reveal system and configuration data to attackers, thus compromising its confidentiality. To properly set the owner of /var/log/audit/*, run the command: $ sudo chown root /var/log/audit/* Is it the case that ? All audit logs must be owned by root user. By default, the path for audit log is
/var/log/audit/
. To properly set the owner of /var/log/audit/*, run the command:
$ sudo chown root /var/log/audit/* 
RHEL-08-030080 file_ownership_var_log_audit_stig
V-230398 162 medium RHEL 8 audit logs must be group-owned by root to prevent unauthorized read access. Unauthorized disclosure of audit records can reveal system and configuration data to attackers, thus compromising its confidentiality. To properly set the group owner of /var/log/audit/*, run the command: $ sudo chgrp root /var/log/audit/* Is it the case that ? All audit logs must be group owned by root user. By default, the path for audit log is
/var/log/audit/
. To properly set the group owner of /var/log/audit/*, run the command:
$ sudo chgrp root /var/log/audit/*
If log_group in /etc/audit/auditd.conf is set to a group other than the root group account, change the group ownership of the audit logs to this specific group.
RHEL-08-030090 file_group_ownership_var_log_audit
V-230399 162 medium RHEL 8 audit log directory must be owned by root to prevent unauthorized read access. Unauthorized disclosure of audit records can reveal system and configuration data to attackers, thus compromising its confidentiality. To properly set the owner of /var/log/audit, run the command: $ sudo chown root /var/log/audit Is it the case that ? All audit directories must be owned by root user. By default, the path for audit log is
/var/log/audit/
. To properly set the owner of /var/log/audit, run the command:
$ sudo chown root /var/log/audit 
RHEL-08-030100 directory_ownership_var_log_audit
V-230400 162 medium RHEL 8 audit log directory must be group-owned by root to prevent unauthorized read access. Unauthorized disclosure of audit records can reveal system and configuration data to attackers, thus compromising its confidentiality. To properly set the group owner of /var/log/audit, run the command: $ sudo chgrp root /var/log/audit Is it the case that ? All audit directories must be group owned by root user. By default, the path for audit log is
/var/log/audit/
. To properly set the group owner of /var/log/audit, run the command:
$ sudo chgrp root /var/log/audit
If log_group in /etc/audit/auditd.conf is set to a group other than the root group account, change the group ownership of the audit directories to this specific group.
RHEL-08-030110 directory_group_ownership_var_log_audit
V-230401 162 medium RHEL 8 audit log directory must have a mode of 0700 or less permissive to prevent unauthorized read access. If users can write to audit logs, audit trails can be modified or destroyed. Run the following command to check the mode of the system audit logs: $ sudo ls -ld /var/log/audit Audit log directories must be mode 0700 or less permissive. Is it the case that any are more permissive? If log_group in /etc/audit/auditd.conf is set to a group other than the root group account, change the mode of the audit log files with the following command:
$ sudo chmod 0750 /var/log/audit

Otherwise, change the mode of the audit log files with the following command:
$ sudo chmod 0700 /var/log/audit
RHEL-08-030120 directory_permissions_var_log_audit
V-230402 162 medium RHEL 8 audit system must protect auditing rules from unauthorized change. Making the audit configuration immutable prevents accidental as well as malicious modification of the audit rules, although it may be problematic if legitimate changes are needed during system operation If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d in order to make the auditd configuration immutable:
-e 2
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file in order to make the auditd configuration immutable:
-e 2
With this setting, a reboot will be required to change any audit rules.
RHEL-08-030121 audit_rules_immutable
V-230403 162 medium RHEL 8 audit system must protect logon UIDs from unauthorized change. If modification of login UIDs is not prevented, they can be changed by unprivileged users and make auditing complicated or impossible. To verify that the Audit is correctly configured according to recommended rules, check the content of the file with the following command: cat /etc/audit/rules.d/11-loginuid.rules The output has to be exactly as follows: ## Make the loginuid immutable. This prevents tampering with the auid. --loginuid-immutable Is it the case that the file does not exist or the content differs? Configure kernel to prevent modification of login UIDs once they are set. Changing login UUIDs while this configuration is enforced requires special capabilities which are not available to unprivileged users. The following rules configure audit as described above:
## Make the loginuid immutable. This prevents tampering with the auid.
--loginuid-immutable

The Audit provides pre-configured rules in /usr/share/audit/sample-rules. The above content can be found in /usr/share/audit/sample-rules/11-loginuid.rules. To deploy this configuration, it is recommended to copy it over to the /etc/audit/rules.d/ directory:
cp /usr/share/audit/sample-rules/11-loginuid.rules /etc/audit/rules.d/
Load new Audit rules into kernel by running:
augenrules --load
RHEL-08-030122 audit_immutable_login_uids
V-230404 169 medium RHEL 8 must generate audit records for all account creations, modifications, disabling, and termination events that affect /etc/shadow. In addition to auditing new user and group accounts, these watches will alert the system administrator(s) to any modifications. Any unexpected users, groups, or modifications should be investigated for legitimacy. To determine if the system is configured to audit account changes, run the following command: auditctl -l | egrep '(/etc/shadow)' If the system is configured to watch for account changes, lines should be returned for each file specified (and with perm=wa for each). Is it the case that the system is not configured to audit account changes? If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d, in order to capture events that modify account changes:

-w /etc/shadow -p wa -k audit_rules_usergroup_modification


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file, in order to capture events that modify account changes:

-w /etc/shadow -p wa -k audit_rules_usergroup_modification
RHEL-08-030130 audit_rules_usergroup_modification_shadow
V-230405 169 medium RHEL 8 must generate audit records for all account creations, modifications, disabling, and termination events that affect /etc/security/opasswd. In addition to auditing new user and group accounts, these watches will alert the system administrator(s) to any modifications. Any unexpected users, groups, or modifications should be investigated for legitimacy. To determine if the system is configured to audit account changes, run the following command: auditctl -l | egrep '(/etc/security/opasswd)' If the system is configured to watch for account changes, lines should be returned for each file specified (and with perm=wa for each). Is it the case that the system is not configured to audit account changes? If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d, in order to capture events that modify account changes:

-w /etc/security/opasswd -p wa -k audit_rules_usergroup_modification


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file, in order to capture events that modify account changes:

-w /etc/security/opasswd -p wa -k audit_rules_usergroup_modification
RHEL-08-030140 audit_rules_usergroup_modification_opasswd
V-230406 169 medium RHEL 8 must generate audit records for all account creations, modifications, disabling, and termination events that affect /etc/passwd. In addition to auditing new user and group accounts, these watches will alert the system administrator(s) to any modifications. Any unexpected users, groups, or modifications should be investigated for legitimacy. To determine if the system is configured to audit account changes, run the following command: auditctl -l | egrep '(/etc/passwd)' If the system is configured to watch for account changes, lines should be returned for each file specified (and with perm=wa for each). Is it the case that the system is not configured to audit account changes? If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d, in order to capture events that modify account changes:

-w /etc/passwd -p wa -k audit_rules_usergroup_modification


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file, in order to capture events that modify account changes:

-w /etc/passwd -p wa -k audit_rules_usergroup_modification
RHEL-08-030150 audit_rules_usergroup_modification_passwd
V-230407 169 medium RHEL 8 must generate audit records for all account creations, modifications, disabling, and termination events that affect /etc/gshadow. In addition to auditing new user and group accounts, these watches will alert the system administrator(s) to any modifications. Any unexpected users, groups, or modifications should be investigated for legitimacy. To determine if the system is configured to audit account changes, run the following command: auditctl -l | egrep '(/etc/gshadow)' If the system is configured to watch for account changes, lines should be returned for each file specified (and with perm=wa for each). Is it the case that the system is not configured to audit account changes? If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d, in order to capture events that modify account changes:

-w /etc/gshadow -p wa -k audit_rules_usergroup_modification


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file, in order to capture events that modify account changes:

-w /etc/gshadow -p wa -k audit_rules_usergroup_modification
RHEL-08-030160 audit_rules_usergroup_modification_gshadow
V-230408 169 medium RHEL 8 must generate audit records for all account creations, modifications, disabling, and termination events that affect /etc/group. In addition to auditing new user and group accounts, these watches will alert the system administrator(s) to any modifications. Any unexpected users, groups, or modifications should be investigated for legitimacy. To determine if the system is configured to audit account changes, run the following command: auditctl -l | egrep '(/etc/group)' If the system is configured to watch for account changes, lines should be returned for each file specified (and with perm=wa for each). Is it the case that the system is not configured to audit account changes? If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d, in order to capture events that modify account changes:

-w /etc/group -p wa -k audit_rules_usergroup_modification


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file, in order to capture events that modify account changes:

-w /etc/group -p wa -k audit_rules_usergroup_modification
RHEL-08-030170 audit_rules_usergroup_modification_group
V-230409 169 medium RHEL 8 must generate audit records for all account creations, modifications, disabling, and termination events that affect /etc/sudoers. The actions taken by system administrators should be audited to keep a record of what was executed on the system, as well as, for accountability purposes. To verify that auditing is configured for system administrator actions, run the following command: $ sudo auditctl -l | grep "watch=/etc/sudoers\|-w /etc/sudoers\" Is it the case that there is not output? At a minimum, the audit system should collect administrator actions for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-w /etc/sudoers -p wa -k actions
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-w /etc/sudoers -p wa -k actions
RHEL-08-030171 audit_rules_sudoers
V-230410 169 medium RHEL 8 must generate audit records for all account creations, modifications, disabling, and termination events that affect /etc/sudoers.d/. The actions taken by system administrators should be audited to keep a record of what was executed on the system, as well as, for accountability purposes. To verify that auditing is configured for system administrator actions, run the following command: $ sudo auditctl -l | grep "watch=/etc/sudoers.d\|-w /etc/sudoers.d" Is it the case that there is not output? At a minimum, the audit system should collect administrator actions for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-w /etc/sudoers.d/ -p wa -k actions
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-w /etc/sudoers.d/ -p wa -k actions
RHEL-08-030172 audit_rules_sudoers_d
V-230411 169 medium The RHEL 8 audit package must be installed. The auditd service is an access monitoring and accounting daemon, watching system calls to audit any access, in comparison with potential local access control policy such as SELinux policy. Run the following command to determine if the audit package is installed: $ rpm -q audit Is it the case that the package is not installed? The audit package should be installed. RHEL-08-030180 package_audit_installed
V-244542 medium RHEL 8 audit records must contain information to establish what type of events occurred, the source of events, where events occurred, and the outcome of events. RHEL-08-030181 Missing Rule
V-230412 169 medium Successful/unsuccessful uses of the su command in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that auditing of privileged command use is configured, run the following command: $ sudo grep su /etc/audit/audit.rules /etc/audit/rules.d/* It should return a relevant line in the audit rules. Is it the case that it is not the case? At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/su -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/su -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030190 audit_rules_privileged_commands_su
V-230413 169 medium The RHEL 8 audit system must be configured to audit any usage of the lremovexattr system call. The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users. To determine if the system is configured to audit calls to the lremovexattr system call, run the following command: preserve$ sudo grep "lremovexattr" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect file permission changes for all users and root.

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S lremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S lremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S lremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S lremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod
RHEL-08-030200 audit_rules_dac_modification_lremovexattr
V-230414 169 medium The RHEL 8 audit system must be configured to audit any usage of the removexattr system call. The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users. To determine if the system is configured to audit calls to the removexattr system call, run the following command: preserve$ sudo grep "removexattr" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect file permission changes for all users and root.

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S removexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S removexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S removexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S removexattr -F auid>=1000 -F auid!=unset -F key=perm_mod
RHEL-08-030210 audit_rules_dac_modification_removexattr
V-230415 169 medium The RHEL 8 audit system must be configured to audit any usage of the lsetxattr system call. The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users. To determine if the system is configured to audit calls to the lsetxattr system call, run the following command: preserve$ sudo grep "lsetxattr" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S lsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S lsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S lsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S lsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
RHEL-08-030220 audit_rules_dac_modification_lsetxattr
V-230416 169 medium The RHEL 8 audit system must be configured to audit any usage of the fsetxattr system call. The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users. To determine if the system is configured to audit calls to the fsetxattr system call, run the following command: preserve$ sudo grep "fsetxattr" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S fsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S fsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fsetxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
RHEL-08-030230 audit_rules_dac_modification_fsetxattr
V-230417 169 medium The RHEL 8 audit system must be configured to audit any usage of the fremovexattr system call. The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users. To determine if the system is configured to audit calls to the fremovexattr system call, run the following command: preserve$ sudo grep "fremovexattr" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect file permission changes for all users and root.

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S fremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S fremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod


If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fremovexattr -F auid>=1000 -F auid!=unset -F key=perm_mod
RHEL-08-030240 audit_rules_dac_modification_fremovexattr
V-230418 169 medium Successful/unsuccessful uses of the chage command in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that auditing of privileged command use is configured, run the following command: $ sudo grep chage /etc/audit/audit.rules /etc/audit/rules.d/* It should return a relevant line in the audit rules. Is it the case that it is not the case? At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/chage -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/chage -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030250 audit_rules_privileged_commands_chage
V-230419 169 medium Successful/unsuccessful uses of the chcon command in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that execution of the command is being audited, run the following command: $ sudo grep "path=/usr/bin/chcon" /etc/audit/audit.rules /etc/audit/rules.d/* The output should return something similar to: -a always,exit -F path=/usr/bin/chcon -F auid>=1000 -F auid!=unset -F key=privileged Is it the case that ? At a minimum, the audit system should collect any execution attempt of the chcon command for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/chcon -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F path=/usr/bin/chcon -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030260 audit_rules_execution_chcon
V-230420 169 medium The RHEL 8 audit system must be configured to audit any usage of the setxattr system call. The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users. To determine if the system is configured to audit calls to the setxattr system call, run the following command: preserve$ sudo grep "setxattr" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S setxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S setxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S setxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S setxattr -F auid>=1000 -F auid!=unset -F key=perm_mod
RHEL-08-030270 audit_rules_dac_modification_setxattr
V-230421 169 medium Successful/unsuccessful uses of the ssh-agent in RHEL 8 must generate an audit record. Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an incident or identify those responsible for one. Audit records can be generated from various components within the information system (e.g., module or policy filter). To verify that execution of the command is being audited, run the following command: $ sudo grep "path=/usr/bin/ssh-agent" /etc/audit/audit.rules /etc/audit/rules.d/* The output should return something similar to: -a always,exit -F path=/usr/bin/ssh-agent -F perm=x -F auid>=1000 -F auid!=unset -k privileged-ssh-agent Is it the case that it is not the case? At a minimum, the audit system should collect any execution attempt of the ssh-agent command for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/ssh-agent -F perm=x -F auid>=1000 -F auid!=unset -k privileged-ssh-agent
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F path=/usr/bin/ssh-agent -F perm=x -F auid>=1000 -F auid!=unset -k privileged-ssh-agent
RHEL-08-030280 audit_rules_privileged_commands_ssh_agent
V-230422 169 medium Successful/unsuccessful uses of the passwd command in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that auditing of privileged command use is configured, run the following command: $ sudo grep passwd /etc/audit/audit.rules /etc/audit/rules.d/* It should return a relevant line in the audit rules. Is it the case that it is not the case? At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/passwd -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/passwd -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030290 audit_rules_privileged_commands_passwd
V-230423 169 medium Successful/unsuccessful uses of the mount command in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that auditing of privileged command use is configured, run the following command: $ sudo grep mount /etc/audit/audit.rules /etc/audit/rules.d/* It should return a relevant line in the audit rules. Is it the case that it is not the case? At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/mount -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/mount -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030300 audit_rules_privileged_commands_mount
V-230424 169 medium Successful/unsuccessful uses of the umount command in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that auditing of privileged command use is configured, run the following command: $ sudo grep umount /etc/audit/audit.rules /etc/audit/rules.d/* It should return a relevant line in the audit rules. Is it the case that it is not the case? At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/umount -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/umount -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030301 audit_rules_privileged_commands_umount
V-230425 169 medium Successful/unsuccessful uses of the mount syscall in RHEL 8 must generate an audit record. The unauthorized exportation of data to external media could result in an information leak where classified information, Privacy Act information, and intellectual property could be lost. An audit trail should be created each time a filesystem is mounted to help identify and guard against information loss. To verify that auditing is configured for all media exportation events, run the following command: $ sudo auditctl -l | grep syscall | grep mount Is it the case that there is no output? At a minimum, the audit system should collect media exportation events for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S mount -F auid>=1000 -F auid!=unset -F key=export
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S mount -F auid>=1000 -F auid!=unset -F key=export
RHEL-08-030302 audit_rules_media_export
V-230426 169 medium Successful/unsuccessful uses of the unix_update in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that auditing of privileged command use is configured, run the following command: $ sudo grep unix_update /etc/audit/audit.rules /etc/audit/rules.d/* It should return a relevant line in the audit rules. Is it the case that it is not the case? At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/sbin/unix_update -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/sbin/unix_update -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030310 audit_rules_privileged_commands_unix_update
V-230427 169 medium Successful/unsuccessful uses of postdrop in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that auditing of privileged command use is configured, run the following command: $ sudo grep postdrop /etc/audit/audit.rules /etc/audit/rules.d/* It should return a relevant line in the audit rules. Is it the case that it is not the case? At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/sbin/postdrop -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/sbin/postdrop -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030311 audit_rules_privileged_commands_postdrop
V-230428 169 medium Successful/unsuccessful uses of postqueue in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that auditing of privileged command use is configured, run the following command: $ sudo grep postqueue /etc/audit/audit.rules /etc/audit/rules.d/* It should return a relevant line in the audit rules. Is it the case that it is not the case? At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/sbin/postqueue -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/sbin/postqueue -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030312 audit_rules_privileged_commands_postqueue
V-230429 169 medium Successful/unsuccessful uses of semanage in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that execution of the command is being audited, run the following command: $ sudo grep "path=/usr/sbin/semanage" /etc/audit/audit.rules /etc/audit/rules.d/* The output should return something similar to: -a always,exit -F path=/usr/sbin/semanage -F auid>=1000 -F auid!=unset -F key=privileged Is it the case that ? At a minimum, the audit system should collect any execution attempt of the semanage command for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/sbin/semanage -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F path=/usr/sbin/semanage -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030313 audit_rules_execution_semanage
V-230430 169 medium Successful/unsuccessful uses of setfiles in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that execution of the command is being audited, run the following command: $ sudo grep "path=/usr/sbin/setfiles" /etc/audit/audit.rules /etc/audit/rules.d/* The output should return something similar to: -a always,exit -F path=/usr/sbin/setfiles -F auid>=1000 -F auid!=unset -F key=privileged Is it the case that ? At a minimum, the audit system should collect any execution attempt of the setfiles command for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/sbin/setfiles -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F path=/usr/sbin/setfiles -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030314 audit_rules_execution_setfiles
V-230431 169 medium Successful/unsuccessful uses of userhelper in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that auditing of privileged command use is configured, run the following command: $ sudo grep userhelper /etc/audit/audit.rules /etc/audit/rules.d/* It should return a relevant line in the audit rules. Is it the case that it is not the case? At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/sbin/userhelper -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/sbin/userhelper -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030315 audit_rules_privileged_commands_userhelper
V-230432 169 medium Successful/unsuccessful uses of setsebool in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that execution of the command is being audited, run the following command: $ sudo grep "path=/usr/sbin/setsebool" /etc/audit/audit.rules /etc/audit/rules.d/* The output should return something similar to: -a always,exit -F path=/usr/sbin/setsebool -F auid>=1000 -F auid!=unset -F key=privileged Is it the case that ? At a minimum, the audit system should collect any execution attempt of the setsebool command for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/sbin/setsebool -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F path=/usr/sbin/setsebool -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030316 audit_rules_execution_setsebool
V-230433 169 medium Successful/unsuccessful uses of unix_chkpwd in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that auditing of privileged command use is configured, run the following command: $ sudo grep unix_chkpwd /etc/audit/audit.rules /etc/audit/rules.d/* It should return a relevant line in the audit rules. Is it the case that it is not the case? At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/sbin/unix_chkpwd -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/sbin/unix_chkpwd -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030317 audit_rules_privileged_commands_unix_chkpwd
V-230434 169 medium Successful/unsuccessful uses of the ssh-keysign in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that auditing of privileged command use is configured, run the following command: $ sudo grep ssh-keysign /etc/audit/audit.rules /etc/audit/rules.d/* It should return a relevant line in the audit rules. Is it the case that it is not the case? At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/libexec/openssh/ssh-keysign -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/libexec/openssh/ssh-keysign -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030320 audit_rules_privileged_commands_ssh_keysign
V-230435 169 medium Successful/unsuccessful uses of the setfacl command in RHEL 8 must generate an audit record. Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an incident or identify those responsible for one. Audit records can be generated from various components within the information system (e.g., module or policy filter). To verify that execution of the command is being audited, run the following command: Configure the operating system to generate an audit record for all uses of the "setfacl" command. Add or update the following rules in the "/etc/audit/audit.rules" file: -a always,exit -F arch=b32 path=/usr/bin/setfacl -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged -a always,exit -F arch=b64 path=/usr/bin/setfacl -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged The audit daemon must be restarted for the changes to take effect. # sudo systemctl restart auditd.service $ sudo grep "path=/usr/bin/setfacl" /etc/audit/audit.rules /etc/audit/rules.d/* The output should return something similar to: -a always,exit -F path=/usr/bin/setfacl -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged Is it the case that ? At a minimum, the audit system should collect any execution attempt of the setfacl command for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/setfacl -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F path=/usr/bin/setfacl -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030330 audit_rules_execution_setfacl
V-230436 169 medium Successful/unsuccessful uses of the pam_timestamp_check command in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that auditing of privileged command use is configured, run the following command: $ sudo grep pam_timestamp_check /etc/audit/audit.rules /etc/audit/rules.d/* It should return a relevant line in the audit rules. Is it the case that it is not the case? At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/sbin/pam_timestamp_check
-F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/sbin/pam_timestamp_check
-F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030340 audit_rules_privileged_commands_pam_timestamp_check
V-230437 169 medium Successful/unsuccessful uses of the newgrp command in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that auditing of privileged command use is configured, run the following command: $ sudo grep newgrp /etc/audit/audit.rules /etc/audit/rules.d/* It should return a relevant line in the audit rules. Is it the case that it is not the case? At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/newgrp -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/newgrp -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030350 audit_rules_privileged_commands_newgrp
V-230438 169 medium Successful/unsuccessful uses of the init_module command in RHEL 8 must generate an audit record. The addition of kernel modules can be used to alter the behavior of the kernel and potentially introduce malicious code into kernel space. It is important to have an audit trail of modules that have been introduced into the kernel. To determine if the system is configured to audit calls to the init_module system call, run the following command: preserve$ sudo grep "init_module" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? To capture kernel module loading events, use following line, setting ARCH to either b32 for 32-bit system, or having two lines for both b32 and b64 in case your system is 64-bit:
-a always,exit -F arch=ARCH -S init_module -F key=modules
Place to add the line depends on a way auditd daemon is configured. If it is configured to use the augenrules program (the default), add the line to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility, add the line to file /etc/audit/audit.rules.
RHEL-08-030360 audit_rules_kernel_module_loading_init
V-230439 169 medium Successful/unsuccessful uses of the rename command in RHEL 8 must generate an audit record. Auditing file deletions will create an audit trail for files that are removed from the system. The audit trail could aid in system troubleshooting, as well as, detecting malicious processes that attempt to delete log files to conceal their presence. To determine if the system is configured to audit calls to the rename system call, run the following command: preserve$ sudo grep "rename" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect file deletion events for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S rename -F auid>=1000 -F auid!=unset -F key=delete
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S rename -F auid>=1000 -F auid!=unset -F key=delete
RHEL-08-030361 audit_rules_file_deletion_events_rename
V-230440 169 medium Successful/unsuccessful uses of the renameat command in RHEL 8 must generate an audit record. Auditing file deletions will create an audit trail for files that are removed from the system. The audit trail could aid in system troubleshooting, as well as, detecting malicious processes that attempt to delete log files to conceal their presence. To determine if the system is configured to audit calls to the renameat system call, run the following command: preserve$ sudo grep "renameat" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect file deletion events for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S renameat -F auid>=1000 -F auid!=unset -F key=delete
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S renameat -F auid>=1000 -F auid!=unset -F key=delete
RHEL-08-030362 audit_rules_file_deletion_events_renameat
V-230441 169 medium Successful/unsuccessful uses of the rmdir command in RHEL 8 must generate an audit record. Auditing file deletions will create an audit trail for files that are removed from the system. The audit trail could aid in system troubleshooting, as well as, detecting malicious processes that attempt to delete log files to conceal their presence. To determine if the system is configured to audit calls to the rmdir system call, run the following command: preserve$ sudo grep "rmdir" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect file deletion events for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S rmdir -F auid>=1000 -F auid!=unset -F key=delete
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S rmdir -F auid>=1000 -F auid!=unset -F key=delete
RHEL-08-030363 audit_rules_file_deletion_events_rmdir
V-230442 169 medium Successful/unsuccessful uses of the unlink command in RHEL 8 must generate an audit record. Auditing file deletions will create an audit trail for files that are removed from the system. The audit trail could aid in system troubleshooting, as well as, detecting malicious processes that attempt to delete log files to conceal their presence. To determine if the system is configured to audit calls to the unlink system call, run the following command: preserve$ sudo grep "unlink" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect file deletion events for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S unlink -F auid>=1000 -F auid!=unset -F key=delete
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S unlink -F auid>=1000 -F auid!=unset -F key=delete
RHEL-08-030364 audit_rules_file_deletion_events_unlink
V-230443 169 medium Successful/unsuccessful uses of the unlinkat command in RHEL 8 must generate an audit record. Auditing file deletions will create an audit trail for files that are removed from the system. The audit trail could aid in system troubleshooting, as well as, detecting malicious processes that attempt to delete log files to conceal their presence. To determine if the system is configured to audit calls to the unlinkat system call, run the following command: preserve$ sudo grep "unlinkat" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect file deletion events for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S unlinkat -F auid>=1000 -F auid!=unset -F key=delete
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S unlinkat -F auid>=1000 -F auid!=unset -F key=delete
RHEL-08-030365 audit_rules_file_deletion_events_unlinkat
V-230444 169 medium Successful/unsuccessful uses of the gpasswd command in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that auditing of privileged command use is configured, run the following command: $ sudo grep gpasswd /etc/audit/audit.rules /etc/audit/rules.d/* It should return a relevant line in the audit rules. Is it the case that it is not the case? At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/gpasswd -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/gpasswd -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030370 audit_rules_privileged_commands_gpasswd
V-230445 169 medium Successful/unsuccessful uses of the finit_module command in RHEL 8 must generate an audit record. The addition/removal of kernel modules can be used to alter the behavior of the kernel and potentially introduce malicious code into kernel space. It is important to have an audit trail of modules that have been introduced into the kernel. To determine if the system is configured to audit calls to the finit_module system call, run the following command: preserve$ sudo grep "finit_module" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d to capture kernel module loading and unloading events, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S finit_module -F key=modules
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file in order to capture kernel module loading and unloading events, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S finit_module -F key=modules
RHEL-08-030380 audit_rules_kernel_module_loading_finit
V-230446 169 medium Successful/unsuccessful uses of the delete_module command in RHEL 8 must generate an audit record. The removal of kernel modules can be used to alter the behavior of the kernel and potentially introduce malicious code into kernel space. It is important to have an audit trail of modules that have been introduced into the kernel. To determine if the system is configured to audit calls to the delete_module system call, run the following command: preserve$ sudo grep "delete_module" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? To capture kernel module unloading events, use following line, setting ARCH to either b32 for 32-bit system, or having two lines for both b32 and b64 in case your system is 64-bit:
-a always,exit -F arch=ARCH -S delete_module -F key=modules
Place to add the line depends on a way auditd daemon is configured. If it is configured to use the augenrules program (the default), add the line to a file with suffix .rules in the directory /etc/audit/rules.d. If the auditd daemon is configured to use the auditctl utility, add the line to file /etc/audit/audit.rules.
RHEL-08-030390 audit_rules_kernel_module_loading_delete
V-230447 169 medium Successful/unsuccessful uses of the crontab command in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that auditing of privileged command use is configured, run the following command: $ sudo grep crontab /etc/audit/audit.rules /etc/audit/rules.d/* It should return a relevant line in the audit rules. Is it the case that it is not the case? At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/crontab -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/crontab -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030400 audit_rules_privileged_commands_crontab
V-230448 169 medium Successful/unsuccessful uses of the chsh command in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that auditing of privileged command use is configured, run the following command: $ sudo grep chsh /etc/audit/audit.rules /etc/audit/rules.d/* It should return a relevant line in the audit rules. Is it the case that it is not the case? At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/chsh -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/chsh -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030410 audit_rules_privileged_commands_chsh
V-230449 169 medium Successful/unsuccessful uses of the truncate command in RHEL 8 must generate an audit record. Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise. To determine if the system is configured to audit calls to the truncate system call, run the following command: preserve$ sudo grep "truncate" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect unauthorized file accesses for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S truncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S truncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S truncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S truncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S truncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S truncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S truncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S truncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
RHEL-08-030420 audit_rules_unsuccessful_file_modification_truncate
V-230450 169 medium Successful/unsuccessful uses of the openat system call in RHEL 8 must generate an audit record. Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise. To determine if the system is configured to audit calls to the openat system call, run the following command: preserve$ sudo grep "openat" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect unauthorized file accesses for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S openat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S openat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S openat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S openat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S openat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S openat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S openat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S openat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
RHEL-08-030430 audit_rules_unsuccessful_file_modification_openat
V-230451 169 medium Successful/unsuccessful uses of the open system call in RHEL 8 must generate an audit record. Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise. To determine if the system is configured to audit calls to the open system call, run the following command: preserve$ sudo grep "open" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect unauthorized file accesses for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S open -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S open -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S open -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S open -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S open -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S open -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S open -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S open -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
RHEL-08-030440 audit_rules_unsuccessful_file_modification_open
V-230452 169 medium Successful/unsuccessful uses of the open_by_handle_at system call in RHEL 8 must generate an audit record. Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise. To determine if the system is configured to audit calls to the open_by_handle_at system call, run the following command: preserve$ sudo grep "open_by_handle_at" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect unauthorized file accesses for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S open_by_handle_at -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S open_by_handle_at -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S open_by_handle_at -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S open_by_handle_at -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S open_by_handle_at,truncate,ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S open_by_handle_at,truncate,ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S open_by_handle_at,truncate,ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S open_by_handle_at,truncate,ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
RHEL-08-030450 audit_rules_unsuccessful_file_modification_open_by_handle_at
V-230453 169 medium Successful/unsuccessful uses of the ftruncate command in RHEL 8 must generate an audit record. Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise. To determine if the system is configured to audit calls to the ftruncate system call, run the following command: preserve$ sudo grep "ftruncate" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect unauthorized file accesses for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S ftruncate -F exiu=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
RHEL-08-030460 audit_rules_unsuccessful_file_modification_ftruncate
V-230454 169 medium Successful/unsuccessful uses of the creat system call in RHEL 8 must generate an audit record. Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise. To determine if the system is configured to audit calls to the creat system call, run the following command: preserve$ sudo grep "creat" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect unauthorized file accesses for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b32 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S creat -F exit=-EACCES -F auid>=1000 -F auid!=unset -F key=access
-a always,exit -F arch=b64 -S creat -F exit=-EPERM -F auid>=1000 -F auid!=unset -F key=access
RHEL-08-030470 audit_rules_unsuccessful_file_modification_creat
V-230455 169 medium Successful/unsuccessful uses of the chown command in RHEL 8 must generate an audit record. The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users. To determine if the system is configured to audit calls to the chown system call, run the following command: preserve$ sudo grep "chown" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S chown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S chown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S chown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S chown -F auid>=1000 -F auid!=unset -F key=perm_mod
RHEL-08-030480 audit_rules_dac_modification_chown
V-230456 169 medium Successful/unsuccessful uses of the chmod command in RHEL 8 must generate an audit record. The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users. To determine if the system is configured to audit calls to the chmod system call, run the following command: preserve$ sudo grep "chmod" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S chmod -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S chmod -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S chmod -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S chmod -F auid>=1000 -F auid!=unset -F key=perm_mod
RHEL-08-030490 audit_rules_dac_modification_chmod
V-230457 169 medium Successful/unsuccessful uses of the lchown system call in RHEL 8 must generate an audit record. The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users. To determine if the system is configured to audit calls to the lchown system call, run the following command: preserve$ sudo grep "lchown" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S lchown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S lchown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S lchown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S lchown -F auid>=1000 -F auid!=unset -F key=perm_mod
RHEL-08-030500 audit_rules_dac_modification_lchown
V-230458 169 medium Successful/unsuccessful uses of the fchownat system call in RHEL 8 must generate an audit record. The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users. To determine if the system is configured to audit calls to the fchownat system call, run the following command: preserve$ sudo grep "fchownat" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S fchownat -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchownat -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S fchownat -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchownat -F auid>=1000 -F auid!=unset -F key=perm_mod
RHEL-08-030510 audit_rules_dac_modification_fchownat
V-230459 169 medium Successful/unsuccessful uses of the fchown system call in RHEL 8 must generate an audit record. The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users. To determine if the system is configured to audit calls to the fchown system call, run the following command: preserve$ sudo grep "fchown" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S fchown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S fchown -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchown -F auid>=1000 -F auid!=unset -F key=perm_mod
RHEL-08-030520 audit_rules_dac_modification_fchown
V-230460 169 medium Successful/unsuccessful uses of the fchmodat system call in RHEL 8 must generate an audit record. The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users. To determine if the system is configured to audit calls to the fchmodat system call, run the following command: preserve$ sudo grep "fchmodat" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S fchmodat -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchmodat -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S fchmodat -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchmodat -F auid>=1000 -F auid!=unset -F key=perm_mod
RHEL-08-030530 audit_rules_dac_modification_fchmodat
V-230461 169 medium Successful/unsuccessful uses of the fchmod system call in RHEL 8 must generate an audit record. The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users. To determine if the system is configured to audit calls to the fchmod system call, run the following command: preserve$ sudo grep "fchmod" /etc/audit/audit.* If the system is configured to audit this activity, it will return a line. Is it the case that no line is returned? At a minimum, the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F arch=b32 -S fchmod -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchmod -F auid>=1000 -F auid!=unset -F key=perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S fchmod -F auid>=1000 -F auid!=unset -F key=perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchmod -F auid>=1000 -F auid!=unset -F key=perm_mod
RHEL-08-030540 audit_rules_dac_modification_fchmod
V-230462 169 medium Successful/unsuccessful uses of the sudo command in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that auditing of privileged command use is configured, run the following command: $ sudo grep sudo /etc/audit/audit.rules /etc/audit/rules.d/* It should return a relevant line in the audit rules. Is it the case that it is not the case? At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/sudo -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/bin/sudo -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030550 audit_rules_privileged_commands_sudo
V-230463 169 medium Successful/unsuccessful uses of the usermod command in RHEL 8 must generate an audit record. Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threats.

Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.
To verify that auditing of privileged command use is configured, run the following command: $ sudo grep usermod /etc/audit/audit.rules /etc/audit/rules.d/* It should return a relevant line in the audit rules. Is it the case that it is not the case? At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/sbin/usermod -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-a always,exit -F path=/usr/sbin/usermod -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030560 audit_rules_privileged_commands_usermod
V-230464 169 medium Successful/unsuccessful uses of the chacl command in RHEL 8 must generate an audit record. Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an incident or identify those responsible for one. Audit records can be generated from various components within the information system (e.g., module or policy filter). To verify that execution of the command is being audited, run the following command: Configure the operating system to generate an audit record for all uses of the "chacl" command. Add or update the following rules in the "/etc/audit/audit.rules" file: -a always,exit -F arch=b32 path=/usr/bin/chacl -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged -a always,exit -F arch=b64 path=/usr/bin/chacl -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged The audit daemon must be restarted for the changes to take effect. # sudo systemctl restart auditd.service Is it the case that ? At a minimum, the audit system should collect any execution attempt of the chacl command for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:
-a always,exit -F path=/usr/bin/chacl -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F path=/usr/bin/chacl -F perm=x -F auid>=1000 -F auid!=unset -F key=privileged
RHEL-08-030570 audit_rules_execution_chacl
V-230465 169 medium Successful/unsuccessful uses of the kmod command in RHEL 8 must generate an audit record. Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an incident or identify those responsible for one. Audit records can be generated from various components within the information system (e.g., module or policy filter). To verify that auditing of privileged command use is configured, run the following command: # sudo grep kmod /etc/audit/audit.rules -w /usr/bin/kmod -p x -k modules If the system is configured to audit the execution of the module management program "kmod", the command will return a line. If the command does not return a line, or the line is commented out, this is a finding. Is it the case that it is not the case? At a minimum, the audit system should collect the execution of privileged commands for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d:
-w /usr/bin/kmod -p x -k modules
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules:
-w /usr/bin/kmod -p x -k modules
RHEL-08-030580 audit_rules_privileged_commands_kmod
V-230466 medium Successful/unsuccessful modifications to the faillock log file in RHEL 8 must generate an audit record. RHEL-08-030590 Missing Rule
V-230467 169 medium Successful/unsuccessful modifications to the lastlog file in RHEL 8 must generate an audit record. Manual editing of these files may indicate nefarious activity, such as an attacker attempting to remove evidence of an intrusion. To verify that auditing is configured for system administrator actions, run the following command: $ sudo auditctl -l | grep "watch=/var/log/lastlog\|-w /var/log/lastlog" Is it the case that there is not output? The audit system already collects login information for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d in order to watch for attempted manual edits of files involved in storing logon events:
-w /var/log/lastlog -p wa -k logins
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file in order to watch for unattempted manual edits of files involved in storing logon events:
-w /var/log/lastlog -p wa -k logins
RHEL-08-030600 audit_rules_login_events_lastlog
V-230468 169 low RHEL 8 must enable auditing of processes that start prior to the audit daemon. Each process on the system carries an "auditable" flag which indicates whether its activities can be audited. Although auditd takes care of enabling this for all processes which launch after it does, adding the kernel argument ensures it is set for every process during boot. Inspect the form of default GRUB 2 command line for the Linux operating system in /boot/grub2/grubenv. If they include audit=1, then auditing is enabled at boot time. # grep 'kernelopts.*audit=1.*' /boot/grub2/grubenv To ensure audit=1 is configured on all installed kernels, the following command may be used: # grub2-editenv - set "$(grub2-editenv - list | grep kernelopts) audit=1" Is it the case that auditing is not enabled at boot time? To ensure all processes can be audited, even those which start prior to the audit daemon, add the argument audit=1 to the default GRUB 2 command line for the Linux operating system in /boot/grub2/grubenv, in the manner below:
# grub2-editenv - set "$(grub2-editenv - list | grep kernelopts) audit=1"
RHEL-08-030601 grub2_audit_argument
V-230469 1849 low RHEL 8 must allocate an audit_backlog_limit of sufficient size to capture processes that start prior to the audit daemon. audit_backlog_limit sets the queue length for audit events awaiting transfer to the audit daemon. Until the audit daemon is up and running, all log messages are stored in this queue. If the queue is overrun during boot process, the action defined by audit failure flag is taken. Inspect the form of default GRUB 2 command line for the Linux operating system in /etc/default/grub. If they include audit=1, then auditing is enabled at boot time. To ensure audit_backlog_limit=8192 is configured on all installed kernels, the following command may be used: $ sudo /sbin/grubby --update-kernel=ALL --args="audit_backlog_limit=8192" Is it the case that audit backlog limit is not configured? To improve the kernel capacity to queue all log events, even those which occurred prior to the audit daemon, add the argument audit_backlog_limit=8192 to the default GRUB 2 command line for the Linux operating system in /etc/default/grub, in the manner below:
GRUB_CMDLINE_LINUX="crashkernel=auto rd.lvm.lv=VolGroup/LogVol06 rd.lvm.lv=VolGroup/lv_swap rhgb quiet rd.shell=0 audit=1 audit_backlog_limit=8192"
RHEL-08-030602 grub2_audit_backlog_limit_argument
V-230470 169 low RHEL 8 must enable Linux audit logging for the USBGuard daemon. Using the Linux Audit logging allows for centralized trace of events. To verify that Linux Audit logging si enabled for the USBGuard daemon, run the following command: $ sudo grep AuditBackend /etc/usbguard/usbguard-daemon.conf The output should be AuditBackend=LinuxAudit Is it the case that AuditBackend is not set to LinuxAudit? To configure USBGuard daemon to log via Linux Audit (as opposed directly to a file), AuditBackend option in /etc/usbguard/usbguard-daemon.conf needs to be set to LinuxAudit. RHEL-08-030603 configure_usbguard_auditbackend
V-230471 171 medium RHEL 8 must allow only the Information System Security Manager (ISSM) (or individuals or roles appointed by the ISSM) to select which auditable events are to be audited. Without the capability to restrict the roles and individuals that can select which events are audited, unauthorized personnel may be able to prevent the auditing of critical events. Misconfigured audits may degrade the system's performance by overwhelming the audit log. Misconfigured audits may also make it more difficult to establish, correlate, and investigate the events relating to an incident or identify those responsible for one. To properly set the permissions of /etc/audit/rules.d/*.rules, run the command:
$ sudo chmod 0640 /etc/audit/rules.d/*.rules
RHEL-08-030610 file_permissions_etc_audit_rulesd
V-230472 medium RHEL 8 audit tools must have a mode of 0755 or less permissive. RHEL-08-030620 Missing Rule
V-230473 medium RHEL 8 audit tools must be owned by root. RHEL-08-030630 Missing Rule
V-230474 medium RHEL 8 audit tools must be group-owned by root. RHEL-08-030640 Missing Rule
V-230475 1496 medium RHEL 8 must use cryptographic mechanisms to protect the integrity of audit tools. Protecting the integrity of the tools used for auditing purposes is a critical step toward ensuring the integrity of audit information. Audit information includes all information (e.g., audit records, audit settings, and audit reports) needed to successfully audit information system activity. Audit tools include but are not limited to vendor-provided and open-source audit tools needed to successfully view and manipulate audit information system activity and records. Audit tools include custom queries and report generators. It is not uncommon for attackers to replace the audit tools or inject code into the existing tools to provide the capability to hide or erase system activity from the audit logs. To address this risk, audit tools must be cryptographically signed to provide the capability to identify when the audit tools have been modified, manipulated, or replaced. An example is a checksum hash of the file or files. Check that AIDE is properly configured to protect the integrity of the audit tools by running the following command: # sudo cat /etc/aide.conf | grep /usr/sbin/au /usr/sbin/auditctl p+i+n+u+g+s+b+acl+selinux+xattrs+sha512 /usr/sbin/auditd p+i+n+u+g+s+b+acl+selinux+xattrs+sha512 /usr/sbin/ausearch p+i+n+u+g+s+b+acl+selinux+xattrs+sha512 /usr/sbin/aureport p+i+n+u+g+s+b+acl+selinux+xattrs+sha512 /usr/sbin/autrace p+i+n+u+g+s+b+acl+selinux+xattrs+sha512 /usr/sbin/audispd p+i+n+u+g+s+b+acl+selinux+xattrs+sha512 /usr/sbin/augenrules p+i+n+u+g+s+b+acl+selinux+xattrs+sha512 If AIDE is configured properly to protect the integrity of the audit tools, all lines listed above will be returned from the command. If one or more lines are missing, this is a finding. Is it the case that integrity checks of the audit tools are missing or incomplete? The operating system file integrity tool must be configured to protect the integrity of the audit tools. RHEL-08-030650 aide_check_audit_tools
V-230476 1849 medium RHEL 8 must allocate audit record storage capacity to store at least one week of audit records, when audit records are not immediately sent to a central audit record storage facility. Information stored in one location is vulnerable to accidental or incidental deletion or alteration.Off-loading is a common process in information systems with limited audit storage capacity. To verify whether audispd plugin off-loads audit records onto a different system or media from the system being audited, run the following command: # grep -i remote_server /etc/audisp/audisp-remote.conf The output should return something similar to where REMOTE_SYSTEM is an IP address or hostname: remote_server = REMOTE_SYSTEM Determine which partition the audit records are being written to with the following command: # grep log_file /etc/audit/auditd.conf log_file = /var/log/audit/audit.log Check the size of the partition that audit records are written to with the following command and verify whether it is sufficiently large: # df -h /var/log/audit/ /dev/sda2 24G 10.4G 13.6G 43% /var/log/audit Is it the case that audispd is not sending logs to a remote system and the local partition has inadequate? The AlmaLinux 8 operating system must allocate audit record storage capacity to store at least one weeks worth of audit records when audit records are not immediately sent to a central audit record storage facility. The partition size needed to capture a week's worth of audit records is based on the activity level of the system and the total storage capacity available. In normal circumstances, 10.0 GB of storage space for audit records will be sufficient. Determine which partition the audit records are being written to with the following command:
# grep log_file /etc/audit/auditd.conf
log_file = /var/log/audit/audit.log
Check the size of the partition that audit records are written to with the following command:
# df -h /var/log/audit/
/dev/sda2 24G 10.4G 13.6G 43% /var/log/audit
RHEL-08-030660 auditd_audispd_configure_sufficiently_large_partition
V-230477 366 medium RHEL 8 must have the packages required for offloading audit logs installed. The rsyslog package provides the rsyslog daemon, which provides system logging services. Run the following command to determine if the rsyslog package is installed: $ rpm -q rsyslog Is it the case that the package is not installed? Rsyslog is installed by default. The rsyslog package can be installed with the following command:
 $ sudo yum install rsyslog
RHEL-08-030670 package_rsyslog_installed
V-230478 366 medium RHEL 8 must have the packages required for encrypting offloaded audit logs installed. The rsyslog-gnutls package provides Transport Layer Security (TLS) support for the rsyslog daemon, which enables secure remote logging. Run the following command to determine if the rsyslog-gnutls package is installed: $ rpm -q rsyslog-gnutls Is it the case that the package is not installed? TLS protocol support for rsyslog is installed. The rsyslog-gnutls package can be installed with the following command:
$ sudo yum install rsyslog-gnutls
RHEL-08-030680 package_rsyslog-gnutls_installed
V-230479 1851 medium The RHEL 8 audit records must be off-loaded onto a different system or storage media from the system being audited. A log server (loghost) receives syslog messages from one or more systems. This data can be used as an additional log source in the event a system is compromised and its local logs are suspect. Forwarding log messages to a remote loghost also provides system administrators with a centralized place to view the status of multiple hosts within the enterprise. To ensure logs are sent to a remote host, examine the file /etc/rsyslog.conf. If using UDP, a line similar to the following should be present: *.* @ If using TCP, a line similar to the following should be present: *.* @@ If using RELP, a line similar to the following should be present: *.* :omrelp: Is it the case that none of these are present? To configure rsyslog to send logs to a remote log server, open /etc/rsyslog.conf and read and understand the last section of the file, which describes the multiple directives necessary to activate remote logging. Along with these other directives, the system can be configured to forward its logs to a particular log server by adding or correcting one of the following lines, substituting appropriately. The choice of protocol depends on the environment of the system; although TCP and RELP provide more reliable message delivery, they may not be supported in all environments.
To use UDP for log message delivery:
*.* @

To use TCP for log message delivery:
*.* @@

To use RELP for log message delivery:
*.* :omrelp:

There must be a resolvable DNS CNAME or Alias record set to "" for logs to be sent correctly to the centralized logging utility.
RHEL-08-030690 rsyslog_remote_loghost
V-230480 1851 medium RHEL 8 must take appropriate action when the internal event queue is full. The audit system should have an action setup in the event the internal event queue becomes full so that no data is lost. Verify the audit system is configured to take an appropriate action when the internal event queue is full: $ sudo grep -i overflow_action /etc/audit/auditd.conf The output should contain be like overflow_action = syslog If the value of the "overflow_action" option is not set to syslog, single, halt or the line is commented out, ask the System Administrator to indicate how the audit logs are off-loaded to a different system or media. Is it the case that auditd overflow action is not setup correctly? The audit system should have an action setup in the event the internal event queue becomes full. To setup an overflow action edit /etc/audit/auditd.conf. Set overflow_action to one of the following values: syslog, single, halt. RHEL-08-030700 auditd_overflow_action
V-230481 1851 medium RHEL 8 must encrypt the transfer of audit records off-loaded onto a different system or media from the system being audited. The audit records generated by Rsyslog contain valuable information regarding system configuration, user authentication, and other such information. Audit records should be protected from unauthorized access. Verify the operating system encrypts audit records off-loaded onto a different system or media from the system being audited with the following commands: $ sudo grep -i '$DefaultNetstreamDriver' /etc/rsyslog.conf /etc/rsyslog.d/*.conf The output should be /etc/rsyslog.conf:$DefaultNetstreamDriver gtls Is it the case that rsyslogd DefaultNetstreamDriver not set to gtls? Rsyslogd is a system utility providing support for message logging. Support for both internet and UNIX domain sockets enables this utility to support both local and remote logging. Couple this utility with gnutls (which is a secure communications library implementing the SSL, TLS and DTLS protocols), and you have a method to securely encrypt and off-load auditing. When using rsyslogd to off-load logs off a encrpytion system must be used. RHEL-08-030710 rsyslog_encrypt_offload_defaultnetstreamdriver
V-230482 1851 medium RHEL 8 must authenticate the remote logging server for off-loading audit logs. The audit records generated by Rsyslog contain valuable information regarding system configuration, user authentication, and other such information. Audit records should be protected from unauthorized access. Verify the operating system authenticates the remote logging server for off-loading audit logs with the following command: $ sudo grep -i '$ActionSendStreamDriverAuthMode' /etc/rsyslog.conf /etc/rsyslog.d/*.conf The output should be $/etc/rsyslog.conf:$ActionSendStreamDriverAuthMode x509/name Is it the case that $ActionSendStreamDriverAuthMode in /etc/rsyslog.conf is not set to x509/name? Rsyslogd is a system utility providing support for message logging. Support for both internet and UNIX domain sockets enables this utility to support both local and remote logging. Couple this utility with gnutls (which is a secure communications library implementing the SSL, TLS and DTLS protocols), and you have a method to securely encrypt and off-load auditing. When using rsyslogd to off-load logs the remote system must be authenticated. RHEL-08-030720 rsyslog_encrypt_offload_actionsendstreamdriverauthmode
V-230483 1855 medium RHEL 8 must take action when allocated audit record storage volume reaches 75 percent of the repository maximum audit record storage capacity. Notifying administrators of an impending disk space problem may allow them to take corrective action prior to any disruption. Inspect /etc/audit/auditd.conf and locate the following line to determine if the system is configured correctly: space_left PERCENTAGE% Is it the case that the system is not configured with a specific percentage to notify administrators of an issue? The auditd service can be configured to take an action when disk space is running low but prior to running out of space completely. Edit the file /etc/audit/auditd.conf. Add or modify the following line, substituting PERCENTAGE appropriately:
space_left = PERCENTAGE%
Set this value to at least 25 to cause the system to notify the user of an issue.
RHEL-08-030730 auditd_data_retention_space_left_percentage
V-244543 1855 medium RHEL 8 must notify the System Administrator (SA) and Information System Security Officer (ISSO) (at a minimum) when allocated audit record storage volume 75 percent utilization. Notifying administrators of an impending disk space problem may allow them to take corrective action prior to any disruption. Inspect /etc/audit/auditd.conf and locate the following line to determine if the system is configured to email the administrator when disk space is starting to run low: $ sudo grep space_left_action /etc/audit/auditd.conf space_left_action Acceptable values are email, suspend, single, and halt. Is it the case that the system is not configured to send an email to the system administrator when disk space is starting to run low? The auditd service can be configured to take an action when disk space starts to run low. Edit the file /etc/audit/auditd.conf. Modify the following line, substituting ACTION appropriately:
space_left_action = ACTION
Possible values for ACTION are described in the auditd.conf man page. These include:
  • syslog
  • email
  • exec
  • suspend
  • single
  • halt
Set this to email (instead of the default, which is suspend) as it is more likely to get prompt attention. Acceptable values also include suspend, single, and halt.
RHEL-08-030731 auditd_data_retention_space_left_action
V-230484 1891 medium RHEL 8 must securely compare internal information system clocks at least every 24 hours with a server synchronized to an authoritative time source, such as the United States Naval Observatory (USNO) time servers, or a time server designated for the appropriate DoD network (NIPRNet/SIPRNet), and/or the Global Positioning System (GPS). Inaccurate time stamps make it more difficult to correlate events and can lead to an inaccurate analysis. Determining the correct time a particular event occurred on a system is critical when conducting forensic analysis and investigating system events. Sources outside the configured acceptable allowance (drift) may be inaccurate. To verify that maxpoll has been set properly, perform the following: $ sudo grep maxpoll /etc/ntp.conf /etc/chrony.conf The output should return maxpoll . Is it the case that it does not exist or maxpoll has not been set to the expected value? The maxpoll should be configured to in /etc/ntp.conf or /etc/chrony.conf to continuously poll time servers. To configure maxpoll in /etc/ntp.conf or /etc/chrony.conf add the following:
maxpoll 
RHEL-08-030740 chronyd_or_ntpd_set_maxpoll
V-230485 381 low RHEL 8 must disable the chrony daemon from acting as a server. Minimizing the exposure of the server functionality of the chrony daemon diminishes the attack surface. To verify that port has been set properly, perform the following: $ grep '\bport\b' /etc/chrony.conf The output should return port 0 Is it the case that it does not exist or port is set to non-zero value? The port option in /etc/chrony.conf can be set to 0 to make chrony daemon to never open any listening port for server operation and to operate strictly in a client-only mode. RHEL-08-030741 chronyd_client_only
V-230486 381 low RHEL 8 must disable network management of the chrony daemon. Not exposing the management interface of the chrony daemon on the network diminishes the attack space. To verify that cmdport has been set properly, perform the following: $ grep '\bcmdport\b' /etc/chrony.conf The output should return cmdport 0 Is it the case that it does not exist or port is set to non-zero value? The cmdport option in /etc/chrony.conf can be set to 0 to stop chrony daemon from listening on the UDP port 323 for management connections made by chronyc. RHEL-08-030742 chronyd_no_chronyc_network
V-230487 381 high RHEL 8 must not have the telnet-server package installed. It is detrimental for operating systems to provide, or install by default, functionality exceeding requirements or mission objectives. These unnecessary capabilities are often overlooked and therefore may remain unsecure. They increase the risk to the platform by providing additional attack vectors.
The telnet service provides an unencrypted remote access service which does not provide for the confidentiality and integrity of user passwords or the remote session. If a privileged user were to login using this service, the privileged user password could be compromised.
Removing the telnet-server package decreases the risk of the telnet service's accidental (or intentional) activation.
Run the following command to determine if the telnet-server package is installed: $ rpm -q telnet-server Is it the case that the package is installed? The telnet-server package can be removed with the following command:
$ sudo yum erase telnet-server
RHEL-08-040000 package_telnet-server_removed
V-230488 381 medium RHEL 8 must not have any automated bug reporting tools installed. Mishandling crash data could expose sensitive information about vulnerabilities in software executing on the system, as well as sensitive information from within a process's address space or registers. Run the following command to determine if the abrt package is installed: $ rpm -q abrt Is it the case that the package is installed? The Automatic Bug Reporting Tool (abrt) collects and reports crash data when an application crash is detected. Using a variety of plugins, abrt can email crash reports to system administrators, log crash reports to files, or forward crash reports to a centralized issue tracking system such as RHTSupport. The abrt package can be removed with the following command:
$ sudo yum erase abrt
RHEL-08-040001 package_abrt_removed
V-230489 381 medium RHEL 8 must not have the sendmail package installed. The sendmail software was not developed with security in mind and its design prevents it from being effectively contained by SELinux. Postfix should be used instead. Run the following command to determine if the sendmail package is installed: $ rpm -q sendmail Is it the case that the package is installed? Sendmail is not the default mail transfer agent and is not installed by default. The sendmail package can be removed with the following command:
$ sudo yum erase sendmail
RHEL-08-040002 package_sendmail_removed
V-230491 381 low RHEL 8 must enable mitigations against processor-based vulnerabilities. Kernel page-table isolation is a kernel feature that mitigates the Meltdown security vulnerability and hardens the kernel against attempts to bypass kernel address space layout randomization (KASLR). Inspect the form of default GRUB 2 command line for the Linux operating system in /etc/default/grub. If they include pti=on, then Kernel page-table isolation is enabled at boot time. To ensure pti=on is configured on all installed kernels, the following command may be used: $ sudo /sbin/grubby --update-kernel=ALL --args="pti=on Is it the case that Kernel page-table isolation is not enabled? To enable Kernel page-table isolation, add the argument pti=on to the default GRUB 2 command line for the Linux operating system in /etc/default/grub, in the manner below:
GRUB_CMDLINE_LINUX="pti=on"
RHEL-08-040004 grub2_pti_argument
V-230492 381 high RHEL 8 must not have the rsh-server package installed. The rsh-server service provides unencrypted remote access service which does not provide for the confidentiality and integrity of user passwords or the remote session and has very weak authentication. If a privileged user were to login using this service, the privileged user password could be compromised. The rsh-server package provides several obsolete and insecure network services. Removing it decreases the risk of those services' accidental (or intentional) activation. Run the following command to determine if the rsh-server package is installed: $ rpm -q rsh-server Is it the case that the package is installed? The rsh-server package can be removed with the following command:
$ sudo yum erase rsh-server
RHEL-08-040010 package_rsh-server_removed
V-230493 medium RHEL 8 must cover or disable the built-in or attached camera when not in use. RHEL-08-040020 Missing Rule
V-230494 381 low RHEL 8 must disable the asynchronous transfer mode (ATM) protocol. Disabling ATM protects the system against exploitation of any flaws in its implementation. If the system is configured to prevent the loading of the atm kernel module, it will contain lines inside any file in /etc/modprobe.d or the deprecated/etc/modprobe.conf. These lines instruct the module loading system to run another program (such as /bin/true) upon a module install event. Run the following command to search for such lines in all files in /etc/modprobe.d and the deprecated /etc/modprobe.conf: $ grep -r atm /etc/modprobe.conf /etc/modprobe.d Is it the case that no line is returned? The Asynchronous Transfer Mode (ATM) is a protocol operating on network, data link, and physical layers, based on virtual circuits and virtual paths. To configure the system to prevent the atm kernel module from being loaded, add the following line to a file in the directory /etc/modprobe.d:
install atm /bin/true
RHEL-08-040021 kernel_module_atm_disabled
V-230495 381 low RHEL 8 must disable the controller area network (CAN) protocol. Disabling CAN protects the system against exploitation of any flaws in its implementation. If the system is configured to prevent the loading of the can kernel module, it will contain lines inside any file in /etc/modprobe.d or the deprecated/etc/modprobe.conf. These lines instruct the module loading system to run another program (such as /bin/true) upon a module install event. Run the following command to search for such lines in all files in /etc/modprobe.d and the deprecated /etc/modprobe.conf: $ grep -r can /etc/modprobe.conf /etc/modprobe.d Is it the case that no line is returned? The Controller Area Network (CAN) is a serial communications protocol which was initially developed for automotive and is now also used in marine, industrial, and medical applications. To configure the system to prevent the can kernel module from being loaded, add the following line to a file in the directory /etc/modprobe.d:
install can /bin/true
RHEL-08-040022 kernel_module_can_disabled
V-230496 381 low RHEL 8 must disable the stream control transmission protocol (SCTP). Disabling SCTP protects the system against exploitation of any flaws in its implementation. If the system is configured to prevent the loading of the sctp kernel module, it will contain lines inside any file in /etc/modprobe.d or the deprecated/etc/modprobe.conf. These lines instruct the module loading system to run another program (such as /bin/true) upon a module install event. Run the following command to search for such lines in all files in /etc/modprobe.d and the deprecated /etc/modprobe.conf: $ grep -r sctp /etc/modprobe.conf /etc/modprobe.d Is it the case that no line is returned? The Stream Control Transmission Protocol (SCTP) is a transport layer protocol, designed to support the idea of message-oriented communication, with several streams of messages within one connection. To configure the system to prevent the sctp kernel module from being loaded, add the following line to a file in the directory /etc/modprobe.d:
install sctp /bin/true
RHEL-08-040023 kernel_module_sctp_disabled
V-230497 381 low RHEL 8 must disable the transparent inter-process communication (TIPC) protocol. Disabling TIPC protects the system against exploitation of any flaws in its implementation. If the system is configured to prevent the loading of the tipc kernel module, it will contain lines inside any file in /etc/modprobe.d or the deprecated/etc/modprobe.conf. These lines instruct the module loading system to run another program (such as /bin/true) upon a module install event. Run the following command to search for such lines in all files in /etc/modprobe.d and the deprecated /etc/modprobe.conf: $ grep -r tipc /etc/modprobe.conf /etc/modprobe.d Is it the case that no line is returned? The Transparent Inter-Process Communication (TIPC) protocol is designed to provide communications between nodes in a cluster. To configure the system to prevent the tipc kernel module from being loaded, add the following line to a file in the directory /etc/modprobe.d:
install tipc /bin/true
RHEL-08-040024 kernel_module_tipc_disabled
V-230498 381 low RHEL 8 must disable mounting of cramfs. Removing support for unneeded filesystem types reduces the local attack surface of the server. If the system is configured to prevent the loading of the cramfs kernel module, it will contain lines inside any file in /etc/modprobe.d or the deprecated/etc/modprobe.conf. These lines instruct the module loading system to run another program (such as /bin/true) upon a module install event. Run the following command to search for such lines in all files in /etc/modprobe.d and the deprecated /etc/modprobe.conf: $ grep -r cramfs /etc/modprobe.conf /etc/modprobe.d Is it the case that no line is returned? To configure the system to prevent the cramfs kernel module from being loaded, add the following line to a file in the directory /etc/modprobe.d:
install cramfs /bin/true
This effectively prevents usage of this uncommon filesystem. The cramfs filesystem type is a compressed read-only Linux filesystem embedded in small footprint systems. A cramfs image can be used without having to first decompress the image.
RHEL-08-040025 kernel_module_cramfs_disabled
V-230499 381 low RHEL 8 must disable IEEE 1394 (FireWire) Support. Disabling FireWire protects the system against exploitation of any flaws in its implementation. If the system is configured to prevent the loading of the firewire-core kernel module, it will contain lines inside any file in /etc/modprobe.d or the deprecated/etc/modprobe.conf. These lines instruct the module loading system to run another program (such as /bin/true) upon a module install event. Run the following command to search for such lines in all files in /etc/modprobe.d and the deprecated /etc/modprobe.conf: $ grep -r firewire-core /etc/modprobe.conf /etc/modprobe.d Is it the case that no line is returned? The IEEE 1394 (FireWire) is a serial bus standard for high-speed real-time communication. To configure the system to prevent the firewire-core kernel module from being loaded, add the following line to a file in the directory /etc/modprobe.d:
install firewire-core /bin/true
RHEL-08-040026 kernel_module_firewire-core_disabled
V-230500 382 medium RHEL 8 must be configured to prohibit or restrict the use of functions, ports, protocols, and/or services, as defined in the Ports, Protocols, and Services Management (PPSM) Category Assignments List (CAL) and vulnerability assessments. In order to prevent unauthorized connection of devices, unauthorized transfer of information, or unauthorized tunneling (i.e., embedding of data types within data types), organizations must disable or restrict unused or unnecessary physical and logical ports/protocols on information systems.

Operating systems are capable of providing a wide variety of functions and services. Some of the functions and services provided by default may not be necessary to support essential organizational operations. Additionally, it is sometimes convenient to provide multiple services from a single component (e.g., VPN and IPS); however, doing so increases risk over limiting the services provided by any one component.

To support the requirements and principles of least functionality, the operating system must support the organizational requirements, providing only essential capabilities and limiting the use of ports, protocols, and/or services to only those required, authorized, and approved to conduct official business or to address authorized quality of life issues.
Inspect the list of enabled firewall ports and verify they are configured correctly by running the following command: $ sudo firewall-cmd --list-all Is it the case that the default rules are not configured? Configure the firewalld ports to allow approved services to have access to the system. To configure firewalld to open ports, run the following command:
$ sudo firewall-cmd --permanent --add-port=port_number/tcp
or
$ sudo firewall-cmd --permanent --add-port=service_name
Run the command list above for each of the ports listed below: To configure firewalld to allow access, run the following command(s): firewall-cmd --permanent --add-service=ssh
RHEL-08-040030 configure_firewalld_ports
V-230502 778 medium The RHEL 8 file system automounter must be disabled unless required. Disabling the automounter permits the administrator to statically control filesystem mounting through /etc/fstab.

Additionally, automatically mounting filesystems permits easy introduction of unknown devices, thereby facilitating malicious activity.
To check that the autofs service is disabled in system boot configuration, run the following command: $ systemctl is-enabled autofs Output should indicate the autofs service has either not been installed, or has been disabled at all runlevels, as shown in the example below: $ systemctl is-enabled autofs disabled Run the following command to verify autofs is not active (i.e. not running) through current runtime configuration: $ systemctl is-active autofs If the service is not running the command will return the following output: inactive The service will also be masked, to check that the autofs is masked, run the following command: $ systemctl show autofs | grep "LoadState\|UnitFileState" If the service is masked the command will return the following outputs: LoadState=masked UnitFileState=masked Is it the case that ? The autofs daemon mounts and unmounts filesystems, such as user home directories shared via NFS, on demand. In addition, autofs can be used to handle removable media, and the default configuration provides the cdrom device as /misc/cd. However, this method of providing access to removable media is not common, so autofs can almost always be disabled if NFS is not in use. Even if NFS is required, it may be possible to configure filesystem mounts statically by editing /etc/fstab rather than relying on the automounter.

The autofs service can be disabled with the following command:
$ sudo systemctl mask --now autofs.service
RHEL-08-040070 service_autofs_disabled
V-230503 778 medium RHEL 8 must be configured to disable USB mass storage. USB storage devices such as thumb drives can be used to introduce malicious software. If the system is configured to prevent the loading of the usb-storage kernel module, it will contain lines inside any file in /etc/modprobe.d or the deprecated/etc/modprobe.conf. These lines instruct the module loading system to run another program (such as /bin/true) upon a module install event. Run the following command to search for such lines in all files in /etc/modprobe.d and the deprecated /etc/modprobe.conf: $ grep -r usb-storage /etc/modprobe.conf /etc/modprobe.d Is it the case that no line is returned? To prevent USB storage devices from being used, configure the kernel module loading system to prevent automatic loading of the USB storage driver. To configure the system to prevent the usb-storage kernel module from being loaded, add the following line to a file in the directory /etc/modprobe.d:
install usb-storage /bin/true
This will prevent the modprobe program from loading the usb-storage module, but will not prevent an administrator (or another program) from using the insmod program to load the module manually.
RHEL-08-040080 kernel_module_usb-storage_disabled
V-230504 medium A RHEL 8 firewall must employ a deny-all, allow-by-exception policy for allowing connections to other systems. RHEL-08-040090 Missing Rule
V-230505 2314 medium A firewall must be installed on RHEL 8. The firewalld package should be installed to provide access control methods. Run the following command to determine if the firewalld package is installed: $ rpm -q firewalld Is it the case that the package is not installed? The firewalld package can be installed with the following command:
$ sudo yum install firewalld
RHEL-08-040100 package_firewalld_installed
V-244544 2314 medium A firewall must be active on RHEL 8. Access control methods provide the ability to enhance system security posture by restricting services and known good IP addresses and address ranges. This prevents connections from unknown hosts and protocols. Run the following command to determine the current status of the firewalld service: $ systemctl is-active firewalld If the service is running, it should return the following: active Is it the case that ? The firewalld service can be enabled with the following command:
$ sudo systemctl enable firewalld.service
RHEL-08-040101 service_firewalld_enabled
V-230506 1444 medium RHEL 8 wireless network adapters must be disabled. The use of wireless networking can introduce many different attack vectors into the organization's network. Common attack vectors such as malicious association and ad hoc networks will allow an attacker to spoof a wireless access point (AP), allowing validated systems to connect to the malicious AP and enabling the attacker to monitor and record network traffic. These malicious APs can also serve to create a man-in-the-middle attack or be used to create a denial of service to valid network resources. Verify that there are no wireless interfaces configured on the system with the following command: $ sudo nmcli device The output should contain the following: wifi disconnected Is it the case that it is not? Deactivating wireless network interfaces should prevent normal usage of the wireless capability.

Configure the system to disable all wireless network interfaces with the following command:
$ sudo nmcli radio wifi off
RHEL-08-040110 wireless_disable_interfaces
V-230507 1443 medium RHEL 8 Bluetooth must be disabled. If Bluetooth functionality must be disabled, preventing the kernel from loading the kernel module provides an additional safeguard against its activation. If the system is configured to prevent the loading of the bluetooth kernel module, it will contain lines inside any file in /etc/modprobe.d or the deprecated/etc/modprobe.conf. These lines instruct the module loading system to run another program (such as /bin/true) upon a module install event. Run the following command to search for such lines in all files in /etc/modprobe.d and the deprecated /etc/modprobe.conf: $ grep -r bluetooth /etc/modprobe.conf /etc/modprobe.d Is it the case that no line is returned? The kernel's module loading system can be configured to prevent loading of the Bluetooth module. Add the following to the appropriate /etc/modprobe.d configuration file to prevent the loading of the Bluetooth module:
install bluetooth /bin/true
RHEL-08-040111 kernel_module_bluetooth_disabled
V-230508 1764 medium RHEL 8 must mount /dev/shm with the nodev option. The only legitimate location for device files is the /dev directory located on the root partition. The only exception to this is chroot jails. To verify the nodev option is configured for the /dev/shm mount point, run the following command: $ mount | grep '\s/dev/shm\s' The output should show the corresponding mount point along with the nodev setting in parentheses. Is it the case that the is not present in the output line, or there is no output line at all? The nodev mount option can be used to prevent creation of device files in /dev/shm. Legitimate character and block devices should not exist within temporary directories like /dev/shm. Add the nodev option to the fourth column of /etc/fstab for the line which controls mounting of /dev/shm. RHEL-08-040120 mount_option_dev_shm_nodev
V-230509 1764 medium RHEL 8 must mount /dev/shm with the nosuid option. The presence of SUID and SGID executables should be tightly controlled. Users should not be able to execute SUID or SGID binaries from temporary storage partitions. To verify the nosuid option is configured for the /dev/shm mount point, run the following command: $ mount | grep '\s/dev/shm\s' The output should show the corresponding mount point along with the nosuid setting in parentheses. Is it the case that the is not present in the output line, or there is no output line at all? The nosuid mount option can be used to prevent execution of setuid programs in /dev/shm. The SUID and SGID permissions should not be required in these world-writable directories. Add the nosuid option to the fourth column of /etc/fstab for the line which controls mounting of /dev/shm. RHEL-08-040121 mount_option_dev_shm_nosuid
V-230510 1764 medium RHEL 8 must mount /dev/shm with the noexec option. Allowing users to execute binaries from world-writable directories such as /dev/shm can expose the system to potential compromise. To verify the noexec option is configured for the /dev/shm mount point, run the following command: $ mount | grep '\s/dev/shm\s' The output should show the corresponding mount point along with the noexec setting in parentheses. Is it the case that the is not present in the output line, or there is no output line at all? The noexec mount option can be used to prevent binaries from being executed out of /dev/shm. It can be dangerous to allow the execution of binaries from world-writable temporary storage directories such as /dev/shm. Add the noexec option to the fourth column of /etc/fstab for the line which controls mounting of /dev/shm. RHEL-08-040122 mount_option_dev_shm_noexec
V-230511 1764 medium RHEL 8 must mount /tmp with the nodev option. The only legitimate location for device files is the /dev directory located on the root partition. The only exception to this is chroot jails. To verify the nodev option is configured for the /tmp mount point, run the following command: $ mount | grep '\s/tmp\s' The output should show the corresponding mount point along with the nodev setting in parentheses. Is it the case that the is not present in the output line, or there is no output line at all? The nodev mount option can be used to prevent device files from being created in /tmp. Legitimate character and block devices should not exist within temporary directories like /tmp. Add the nodev option to the fourth column of /etc/fstab for the line which controls mounting of /tmp. RHEL-08-040123 mount_option_tmp_nodev
V-230512 1764 medium RHEL 8 must mount /tmp with the nosuid option. The presence of SUID and SGID executables should be tightly controlled. Users should not be able to execute SUID or SGID binaries from temporary storage partitions. To verify the nosuid option is configured for the /tmp mount point, run the following command: $ mount | grep '\s/tmp\s' The output should show the corresponding mount point along with the nosuid setting in parentheses. Is it the case that the is not present in the output line, or there is no output line at all? The nosuid mount option can be used to prevent execution of setuid programs in /tmp. The SUID and SGID permissions should not be required in these world-writable directories. Add the nosuid option to the fourth column of /etc/fstab for the line which controls mounting of /tmp. RHEL-08-040124 mount_option_tmp_nosuid
V-230513 1764 medium RHEL 8 must mount /tmp with the noexec option. Allowing users to execute binaries from world-writable directories such as /tmp should never be necessary in normal operation and can expose the system to potential compromise. To verify the noexec option is configured for the /tmp mount point, run the following command: $ mount | grep '\s/tmp\s' The output should show the corresponding mount point along with the noexec setting in parentheses. Is it the case that the is not present in the output line, or there is no output line at all? The noexec mount option can be used to prevent binaries from being executed out of /tmp. Add the noexec option to the fourth column of /etc/fstab for the line which controls mounting of /tmp. RHEL-08-040125 mount_option_tmp_noexec
V-230514 1764 medium RHEL 8 must mount /var/log with the nodev option. The only legitimate location for device files is the /dev directory located on the root partition. The only exception to this is chroot jails. To verify the nodev option is configured for the /var/log mount point, run the following command: $ mount | grep '\s/var/log\s' The output should show the corresponding mount point along with the nodev setting in parentheses. Is it the case that the is not present in the output line, or there is no output line at all? The nodev mount option can be used to prevent device files from being created in /var/log. Legitimate character and block devices should exist only in the /dev directory on the root partition or within chroot jails built for system services. Add the nodev option to the fourth column of /etc/fstab for the line which controls mounting of /var/log. RHEL-08-040126 mount_option_var_log_nodev
V-230515 1764 medium RHEL 8 must mount /var/log with the nosuid option. The presence of SUID and SGID executables should be tightly controlled. Users should not be able to execute SUID or SGID binaries from partitions designated for log files. To verify the nosuid option is configured for the /var/log mount point, run the following command: $ mount | grep '\s/var/log\s' The output should show the corresponding mount point along with the nosuid setting in parentheses. Is it the case that the is not present in the output line, or there is no output line at all? The nosuid mount option can be used to prevent execution of setuid programs in /var/log. The SUID and SGID permissions should not be required in directories containing log files. Add the nosuid option to the fourth column of /etc/fstab for the line which controls mounting of /var/log. RHEL-08-040127 mount_option_var_log_nosuid
V-230516 1764 medium RHEL 8 must mount /var/log with the noexec option. Allowing users to execute binaries from directories containing log files such as /var/log should never be necessary in normal operation and can expose the system to potential compromise. To verify the noexec option is configured for the /var/log mount point, run the following command: $ mount | grep '\s/var/log\s' The output should show the corresponding mount point along with the noexec setting in parentheses. Is it the case that the is not present in the output line, or there is no output line at all? The noexec mount option can be used to prevent binaries from being executed out of /var/log. Add the noexec option to the fourth column of /etc/fstab for the line which controls mounting of /var/log. RHEL-08-040128 mount_option_var_log_noexec
V-230517 1764 medium RHEL 8 must mount /var/log/audit with the nodev option. The only legitimate location for device files is the /dev directory located on the root partition. The only exception to this is chroot jails. To verify the nodev option is configured for the /var/log/audit mount point, run the following command: $ mount | grep '\s/var/log/audit\s' The output should show the corresponding mount point along with the nodev setting in parentheses. Is it the case that the is not present in the output line, or there is no output line at all? The nodev mount option can be used to prevent device files from being created in /var/log/audit. Legitimate character and block devices should exist only in the /dev directory on the root partition or within chroot jails built for system services. Add the nodev option to the fourth column of /etc/fstab for the line which controls mounting of /var/log/audit. RHEL-08-040129 mount_option_var_log_audit_nodev
V-230518 1764 medium RHEL 8 must mount /var/log/audit with the nosuid option. The presence of SUID and SGID executables should be tightly controlled. Users should not be able to execute SUID or SGID binaries from partitions designated for audit log files. To verify the nosuid option is configured for the /var/log/audit mount point, run the following command: $ mount | grep '\s/var/log/audit\s' The output should show the corresponding mount point along with the nosuid setting in parentheses. Is it the case that the is not present in the output line, or there is no output line at all? The nosuid mount option can be used to prevent execution of setuid programs in /var/log/audit. The SUID and SGID permissions should not be required in directories containing audit log files. Add the nosuid option to the fourth column of /etc/fstab for the line which controls mounting of /var/log/audit. RHEL-08-040130 mount_option_var_log_audit_nosuid
V-230519 1764 medium RHEL 8 must mount /var/log/audit with the noexec option. Allowing users to execute binaries from directories containing audit log files such as /var/log/audit should never be necessary in normal operation and can expose the system to potential compromise. To verify the noexec option is configured for the /var/log/audit mount point, run the following command: $ mount | grep '\s/var/log/audit\s' The output should show the corresponding mount point along with the noexec setting in parentheses. Is it the case that the is not present in the output line, or there is no output line at all? The noexec mount option can be used to prevent binaries from being executed out of /var/log/audit. Add the noexec option to the fourth column of /etc/fstab for the line which controls mounting of /var/log/audit. RHEL-08-040131 mount_option_var_log_audit_noexec
V-230520 1764 medium RHEL 8 must mount /var/tmp with the nodev option. The only legitimate location for device files is the /dev directory located on the root partition. The only exception to this is chroot jails. To verify the nodev option is configured for the /var/tmp mount point, run the following command: $ mount | grep '\s/var/tmp\s' The output should show the corresponding mount point along with the nodev setting in parentheses. Is it the case that the is not present in the output line, or there is no output line at all? The nodev mount option can be used to prevent device files from being created in /var/tmp. Legitimate character and block devices should not exist within temporary directories like /var/tmp. Add the nodev option to the fourth column of /etc/fstab for the line which controls mounting of /var/tmp. RHEL-08-040132 mount_option_var_tmp_nodev
V-230521 1764 medium RHEL 8 must mount /var/tmp with the nosuid option. The presence of SUID and SGID executables should be tightly controlled. Users should not be able to execute SUID or SGID binaries from temporary storage partitions. To verify the nosuid option is configured for the /var/tmp mount point, run the following command: $ mount | grep '\s/var/tmp\s' The output should show the corresponding mount point along with the nosuid setting in parentheses. Is it the case that the is not present in the output line, or there is no output line at all? The nosuid mount option can be used to prevent execution of setuid programs in /var/tmp. The SUID and SGID permissions should not be required in these world-writable directories. Add the nosuid option to the fourth column of /etc/fstab for the line which controls mounting of /var/tmp. RHEL-08-040133 mount_option_var_tmp_nosuid
V-230522 1764 medium RHEL 8 must mount /var/tmp with the noexec option. Allowing users to execute binaries from world-writable directories such as /var/tmp should never be necessary in normal operation and can expose the system to potential compromise. To verify the noexec option is configured for the /var/tmp mount point, run the following command: $ mount | grep '\s/var/tmp\s' The output should show the corresponding mount point along with the noexec setting in parentheses. Is it the case that the is not present in the output line, or there is no output line at all? The noexec mount option can be used to prevent binaries from being executed out of /var/tmp. Add the noexec option to the fourth column of /etc/fstab for the line which controls mounting of /var/tmp. RHEL-08-040134 mount_option_var_tmp_noexec
V-230523 1764 medium The RHEL 8 fapolicy module must be installed. fapolicyd (File Access Policy Daemon) implements application whitelisting to decide file access rights. Run the following command to determine if the fapolicyd package is installed: $ rpm -q fapolicyd Is it the case that the package is not installed? The fapolicyd package can be installed with the following command:
$ sudo yum install fapolicyd
RHEL-08-040135 package_fapolicyd_installed
V-244545 1764 medium The RHEL 8 fapolicy module must be enabled. The fapolicyd service (File Access Policy Daemon) implements application whitelisting to decide file access rights. Run the following command to determine the current status of the fapolicyd service: $ systemctl is-active fapolicyd If the service is running, it should return the following: active Is it the case that the service is not enabled? The File Access Policy service should be enabled. The fapolicyd service can be enabled with the following command:
$ sudo systemctl enable fapolicyd.service
RHEL-08-040136 service_fapolicyd_enabled
V-244546 medium The RHEL 8 fapolicy module must be configured to employ a deny-all, permit-by-exception policy to allow the execution of authorized software programs. RHEL-08-040137 Missing Rule
V-244547 1958 medium RHEL 8 must have the USBGuard installed. usbguard is a software framework that helps to protect against rogue USB devices by implementing basic whitelisting/blacklisting capabilities based on USB device attributes. Run the following command to determine if the usbguard package is installed: $ rpm -q usbguard Is it the case that the package is not installed? The usbguard package can be installed with the following command:
$ sudo yum install usbguard
RHEL-08-040139 package_usbguard_installed
V-230524 1958 medium RHEL 8 must block unauthorized peripherals before establishing a connection. The usbguard must be configured to allow connected USB devices to work properly, avoiding the system to become inaccessible. Check that the file /etc/usbguard/rules.conf exists and contains a valid configuration Is it the case that /etc/usbguard/rules.conf does not exist or is empty? By default USBGuard when enabled prevents access to all USB devices and this lead to inaccessible system if they use USB mouse/keyboard. To prevent this scenario, the initial policy configuration must be generated based on current connected USB devices. RHEL-08-040140 usbguard_generate_policy
V-244548 1958 medium RHEL 8 must enable the USBGuard. The usbguard service must be running in order to enforce the USB device authorization policy for all USB devices. Run the following command to determine the current status of the usbguard service: $ systemctl is-active usbguard If the service is running, it should return the following: active Is it the case that the service is not enabled? The USBGuard service should be enabled. The usbguard service can be enabled with the following command:
$ sudo systemctl enable usbguard.service
RHEL-08-040141 service_usbguard_enabled
V-230525 medium A firewall must be able to protect against or limit the effects of Denial of Service (DoS) attacks by ensuring RHEL 8 can implement rate-limiting measures on impacted network interfaces. RHEL-08-040150 Missing Rule
V-244549 2418 medium All RHEL 8 networked systems must have SSH installed. Without protection of the transmitted information, confidentiality, and integrity may be compromised because unprotected communications can be intercepted and either read or altered. Run the following command to determine if the openssh-server package is installed: $ rpm -q openssh-server Is it the case that the package is not installed? The openssh-server package should be installed. The openssh-server package can be installed with the following command:
$ sudo yum install openssh-server
RHEL-08-040159 package_openssh-server_installed
V-230526 2418 medium All RHEL 8 networked systems must have and implement SSH to protect the confidentiality and integrity of transmitted and received information, as well as information during preparation for transmission. Without protection of the transmitted information, confidentiality, and integrity may be compromised because unprotected communications can be intercepted and either read or altered.

This checklist item applies to both internal and external networks and all types of information system components from which information can be transmitted (e.g., servers, mobile devices, notebook computers, printers, copiers, scanners, etc). Communication paths outside the physical protection of a controlled boundary are exposed to the possibility of interception and modification.
Run the following command to determine the current status of the sshd service: $ systemctl is-active sshd If the service is running, it should return the following: active Is it the case that ? The SSH server service, sshd, is commonly needed. The sshd service can be enabled with the following command:
$ sudo systemctl enable sshd.service
RHEL-08-040160 service_sshd_enabled
V-230527 68 medium RHEL 8 must force a frequent session key renegotiation for SSH connections to the server. By decreasing the limit based on the amount of data and enabling time-based limit, effects of potential attacks against encryption keys are limited. To check if RekeyLimit is set correctly, run the following command: $ sudo grep RekeyLimit /etc/ssh/sshd_config If configured properly, output should be RekeyLimit Is it the case that it is commented out or is not set? The RekeyLimit parameter specifies how often the session key of the is renegotiated, both in terms of amount of data that may be transmitted and the time elapsed. To decrease the default limits, put line RekeyLimit to file /etc/ssh/sshd_config. RHEL-08-040161 sshd_rekey_limit
V-230529 366 high The x86 Ctrl-Alt-Delete key sequence must be disabled on RHEL 8. A locally logged-in user who presses Ctrl-Alt-Del, when at the console, can reboot the system. If accidentally pressed, as could happen in the case of mixed OS environment, this can create the risk of short-term loss of availability of systems due to unintentional reboot. To ensure the system is configured to mask the Ctrl-Alt-Del sequence, Check that the ctrl-alt-del.target is masked and not active with the following command: sudo systemctl status ctrl-alt-del.target The output should indicate that the target is masked and not active. It might resemble following output: ctrl-alt-del.target Loaded: masked (/dev/null; bad) Active: inactive (dead) Is it the case that the system is configured to reboot when Ctrl-Alt-Del is pressed? By default, SystemD will reboot the system if the Ctrl-Alt-Del key sequence is pressed.

To configure the system to ignore the Ctrl-Alt-Del key sequence from the command line instead of rebooting the system, do either of the following:
ln -sf /dev/null /etc/systemd/system/ctrl-alt-del.target
or
systemctl mask ctrl-alt-del.target


Do not simply delete the /usr/lib/systemd/system/ctrl-alt-del.service file, as this file may be restored during future system updates.
RHEL-08-040170 disable_ctrlaltdel_reboot
V-230530 366 high The x86 Ctrl-Alt-Delete key sequence in RHEL 8 must be disabled if a graphical user interface is installed. A locally logged-in user who presses Ctrl-Alt-Del, when at the console, can reboot the system. If accidentally pressed, as could happen in the case of mixed OS environment, this can create the risk of short-term loss of availability of systems due to unintentional reboot. To ensure the system is configured to ignore the Ctrl-Alt-Del sequence, run the following command: $ gsettings get org.gnome.settings-daemon.plugins.media-keys logout If properly configured, the output should be ''. To ensure that users cannot enable the Ctrl-Alt-Del sequence, run the following: $ grep logout /etc/dconf/db/local.d/locks/* If properly configured, the output should be /org/gnome/settings-daemon/plugins/media-keys/logout Is it the case that GNOME3 is configured to reboot when Ctrl-Alt-Del is pressed? By default, GNOME will reboot the system if the Ctrl-Alt-Del key sequence is pressed.

To configure the system to ignore the Ctrl-Alt-Del key sequence from the Graphical User Interface (GUI) instead of rebooting the system, add or set logout to '' in /etc/dconf/db/local.d/00-security-settings. For example:
[org/gnome/settings-daemon/plugins/media-keys]
logout=''
Once the settings have been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/settings-daemon/plugins/media-keys/logout
After the settings have been set, run dconf update.
RHEL-08-040171 dconf_gnome_disable_ctrlaltdel_reboot
V-230531 366 high The systemd Ctrl-Alt-Delete burst key sequence in RHEL 8 must be disabled. A locally logged-in user who presses Ctrl-Alt-Del, when at the console, can reboot the system. If accidentally pressed, as could happen in the case of mixed OS environment, this can create the risk of short-term loss of availability of systems due to unintentional reboot. To ensure the system is configured to ignore the Ctrl-Alt-Del setting, enter the following command: $ sudo grep -i ctrlaltdelburstaction /etc/systemd/system.conf The output should return: CtrlAltDelBurstAction=none Is it the case that the system is configured to reboot when Ctrl-Alt-Del is pressed more than 7 times in 2 seconds.? By default, SystemD will reboot the system if the Ctrl-Alt-Del key sequence is pressed Ctrl-Alt-Delete more than 7 times in 2 seconds.

To configure the system to ignore the CtrlAltDelBurstAction setting, add or modify the following to /etc/systemd/system.conf:
CtrlAltDelBurstAction=none
RHEL-08-040172 disable_ctrlaltdel_burstaction
V-230532 366 medium The debug-shell systemd service must be disabled on RHEL 8. This prevents attackers with physical access from trivially bypassing security on the machine through valid troubleshooting configurations and gaining root access when the system is rebooted. To check that the debug-shell service is disabled in system boot configuration, run the following command: $ systemctl is-enabled debug-shell Output should indicate the debug-shell service has either not been installed, or has been disabled at all runlevels, as shown in the example below: $ systemctl is-enabled debug-shell disabled Run the following command to verify debug-shell is not active (i.e. not running) through current runtime configuration: $ systemctl is-active debug-shell If the service is not running the command will return the following output: inactive The service will also be masked, to check that the debug-shell is masked, run the following command: $ systemctl show debug-shell | grep "LoadState\|UnitFileState" If the service is masked the command will return the following outputs: LoadState=masked UnitFileState=masked Is it the case that ? SystemD's debug-shell service is intended to diagnose SystemD related boot issues with various systemctl commands. Once enabled and following a system reboot, the root shell will be available on tty9 which is access by pressing CTRL-ALT-F9. The debug-shell service should only be used for SystemD related issues and should otherwise be disabled.

By default, the debug-shell SystemD service is already disabled. The debug-shell service can be disabled with the following command:
$ sudo systemctl mask --now debug-shell.service
RHEL-08-040180 service_debug-shell_disabled
V-230533 366 high The Trivial File Transfer Protocol (TFTP) server package must not be installed if not required for RHEL 8 operational support. Removing the tftp-server package decreases the risk of the accidental (or intentional) activation of tftp services.

If TFTP is required for operational support (such as transmission of router configurations), its use must be documented with the Information Systems Securty Manager (ISSM), restricted to only authorized personnel, and have access control rules established.
Run the following command to determine if the tftp-server package is installed: $ rpm -q tftp-server Is it the case that the package is installed? The tftp-server package can be removed with the following command:
 $ sudo yum erase tftp-server
RHEL-08-040190 package_tftp-server_removed
V-230534 366 high The root account must be the only account having unrestricted access to the RHEL 8 system. An account has root authority if it has a UID of 0. Multiple accounts with a UID of 0 afford more opportunity for potential intruders to guess a password for a privileged account. Proper configuration of sudo is recommended to afford multiple system administrators access to root privileges in an accountable manner. To list all password file entries for accounts with UID 0, run the following command: $ awk -F: '($3 == \"0\") {print}' /etc/passwd This should print only one line, for the user root. If there is a finding, change the UID of the failing (non-root) user. If the account is associated with the system commands or applications the UID should be changed to one greater than 0 but less than 1000. Otherwise assign a UID of greater than 1000 that has not already been assigned. Is it the case that any account other than root has a UID of 0? If any account other than root has a UID of 0, this misconfiguration should be investigated and the accounts other than root should be removed or have their UID changed.
If the account is associated with system commands or applications the UID should be changed to one greater than "0" but less than "1000." Otherwise assign a UID greater than "1000" that has not already been assigned.
RHEL-08-040200 accounts_no_uid_except_zero
V-244550 366 medium RHEL 8 must prevent IPv4 Internet Control Message Protocol (ICMP) redirect messages from being accepted. ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages modify the host's route table and are unauthenticated. An illicit ICMP redirect message could result in a man-in-the-middle attack.
This feature of the IPv4 protocol has few legitimate uses. It should be disabled unless absolutely required.
The runtime status of the net.ipv4.conf.default.accept_redirects kernel parameter can be queried by running the following command: $ sysctl net.ipv4.conf.default.accept_redirects The output of the command should indicate a value of 0. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*net.ipv4.conf.default.accept_redirects\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than net.ipv4.conf.default.accept_redirects = 0 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains net.ipv4.conf.default.accept_redirects = 0, and that one assignment is returned when $ grep -r net.ipv4.conf.default.accept_redirects /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the net.ipv4.conf.default.accept_redirects kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.conf.default.accept_redirects=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.conf.default.accept_redirects = 0
RHEL-08-040209 sysctl_net_ipv4_conf_default_accept_redirects
V-230535 366 medium RHEL 8 must prevent IPv6 Internet Control Message Protocol (ICMP) redirect messages from being accepted. An illicit ICMP redirect message could result in a man-in-the-middle attack. The runtime status of the net.ipv6.conf.default.accept_redirects kernel parameter can be queried by running the following command: $ sysctl net.ipv6.conf.default.accept_redirects The output of the command should indicate a value of 0. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*net.ipv6.conf.default.accept_redirects\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than net.ipv6.conf.default.accept_redirects = 0 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains net.ipv6.conf.default.accept_redirects = 0, and that one assignment is returned when $ grep -r net.ipv6.conf.default.accept_redirects /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the net.ipv6.conf.default.accept_redirects kernel parameter, run the following command:
$ sudo sysctl -w net.ipv6.conf.default.accept_redirects=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv6.conf.default.accept_redirects = 0
RHEL-08-040210 sysctl_net_ipv6_conf_default_accept_redirects
V-230536 366 medium RHEL 8 must not send Internet Control Message Protocol (ICMP) redirects. ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages contain information from the system's route table possibly revealing portions of the network topology.
The ability to send ICMP redirects is only appropriate for systems acting as routers.
The runtime status of the net.ipv4.conf.all.send_redirects kernel parameter can be queried by running the following command: $ sysctl net.ipv4.conf.all.send_redirects The output of the command should indicate a value of 0. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*net.ipv4.conf.all.send_redirects\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than net.ipv4.conf.all.send_redirects = 0 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains net.ipv4.conf.all.send_redirects = 0, and that one assignment is returned when $ grep -r net.ipv4.conf.all.send_redirects /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the net.ipv4.conf.all.send_redirects kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.conf.all.send_redirects=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.conf.all.send_redirects = 0
RHEL-08-040220 sysctl_net_ipv4_conf_all_send_redirects
V-230537 366 medium RHEL 8 must not respond to Internet Control Message Protocol (ICMP) echoes sent to a broadcast address. Responding to broadcast (ICMP) echoes facilitates network mapping and provides a vector for amplification attacks.
Ignoring ICMP echo requests (pings) sent to broadcast or multicast addresses makes the system slightly more difficult to enumerate on the network.
The runtime status of the net.ipv4.icmp_echo_ignore_broadcasts kernel parameter can be queried by running the following command: $ sysctl net.ipv4.icmp_echo_ignore_broadcasts The output of the command should indicate a value of 1. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*net.ipv4.icmp_echo_ignore_broadcasts\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than net.ipv4.icmp_echo_ignore_broadcasts = 1 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains net.ipv4.icmp_echo_ignore_broadcasts = 1, and that one assignment is returned when $ grep -r net.ipv4.icmp_echo_ignore_broadcasts /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the net.ipv4.icmp_echo_ignore_broadcasts kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.icmp_echo_ignore_broadcasts=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.icmp_echo_ignore_broadcasts = 1
RHEL-08-040230 sysctl_net_ipv4_icmp_echo_ignore_broadcasts
V-244551 366 medium RHEL 8 must not forward IPv4 source-routed packets. Source-routed packets allow the source of the packet to suggest routers forward the packet along a different path than configured on the router, which can be used to bypass network security measures. This requirement applies only to the forwarding of source-routerd traffic, such as when IPv4 forwarding is enabled and the system is functioning as a router.

Accepting source-routed packets in the IPv4 protocol has few legitimate uses. It should be disabled unless it is absolutely required.
The runtime status of the net.ipv4.conf.all.accept_source_route kernel parameter can be queried by running the following command: $ sysctl net.ipv4.conf.all.accept_source_route The output of the command should indicate a value of 0. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*net.ipv4.conf.all.accept_source_route\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than net.ipv4.conf.all.accept_source_route = 0 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains net.ipv4.conf.all.accept_source_route = 0, and that one assignment is returned when $ grep -r net.ipv4.conf.all.accept_source_route /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the net.ipv4.conf.all.accept_source_route kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.conf.all.accept_source_route=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.conf.all.accept_source_route = 0
RHEL-08-040239 sysctl_net_ipv4_conf_all_accept_source_route
V-230538 366 medium RHEL 8 must not forward IPv6 source-routed packets. Source-routed packets allow the source of the packet to suggest routers forward the packet along a different path than configured on the router, which can be used to bypass network security measures. This requirement applies only to the forwarding of source-routerd traffic, such as when IPv6 forwarding is enabled and the system is functioning as a router.

Accepting source-routed packets in the IPv6 protocol has few legitimate uses. It should be disabled unless it is absolutely required.
The runtime status of the net.ipv6.conf.all.accept_source_route kernel parameter can be queried by running the following command: $ sysctl net.ipv6.conf.all.accept_source_route The output of the command should indicate a value of 0. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*net.ipv6.conf.all.accept_source_route\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than net.ipv6.conf.all.accept_source_route = 0 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains net.ipv6.conf.all.accept_source_route = 0, and that one assignment is returned when $ grep -r net.ipv6.conf.all.accept_source_route /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the net.ipv6.conf.all.accept_source_route kernel parameter, run the following command:
$ sudo sysctl -w net.ipv6.conf.all.accept_source_route=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv6.conf.all.accept_source_route = 0
RHEL-08-040240 sysctl_net_ipv6_conf_all_accept_source_route
V-244552 366 medium RHEL 8 must not forward IPv4 source-routed packets by default. Source-routed packets allow the source of the packet to suggest routers forward the packet along a different path than configured on the router, which can be used to bypass network security measures.
Accepting source-routed packets in the IPv4 protocol has few legitimate uses. It should be disabled unless it is absolutely required, such as when IPv4 forwarding is enabled and the system is legitimately functioning as a router.
The runtime status of the net.ipv4.conf.default.accept_source_route kernel parameter can be queried by running the following command: $ sysctl net.ipv4.conf.default.accept_source_route The output of the command should indicate a value of 0. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*net.ipv4.conf.default.accept_source_route\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than net.ipv4.conf.default.accept_source_route = 0 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains net.ipv4.conf.default.accept_source_route = 0, and that one assignment is returned when $ grep -r net.ipv4.conf.default.accept_source_route /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the net.ipv4.conf.default.accept_source_route kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.conf.default.accept_source_route=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.conf.default.accept_source_route = 0
RHEL-08-040249 sysctl_net_ipv4_conf_default_accept_source_route
V-230539 366 medium RHEL 8 must not forward IPv6 source-routed packets by default. Source-routed packets allow the source of the packet to suggest routers forward the packet along a different path than configured on the router, which can be used to bypass network security measures. This requirement applies only to the forwarding of source-routerd traffic, such as when IPv6 forwarding is enabled and the system is functioning as a router. Accepting source-routed packets in the IPv6 protocol has few legitimate uses. It should be disabled unless it is absolutely required. The runtime status of the net.ipv6.conf.default.accept_source_route kernel parameter can be queried by running the following command: $ sysctl net.ipv6.conf.default.accept_source_route The output of the command should indicate a value of 0. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*net.ipv6.conf.default.accept_source_route\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than net.ipv6.conf.default.accept_source_route = 0 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains net.ipv6.conf.default.accept_source_route = 0, and that one assignment is returned when $ grep -r net.ipv6.conf.default.accept_source_route /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the net.ipv6.conf.default.accept_source_route kernel parameter, run the following command:
$ sudo sysctl -w net.ipv6.conf.default.accept_source_route=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv6.conf.default.accept_source_route = 0
RHEL-08-040250 sysctl_net_ipv6_conf_default_accept_source_route
V-230540 366 medium RHEL 8 must not be performing packet forwarding unless the system is a router. Routing protocol daemons are typically used on routers to exchange network topology information with other routers. If this capability is used when not required, system network information may be unnecessarily transmitted across the network. The runtime status of the net.ipv4.ip_forward kernel parameter can be queried by running the following command: $ sysctl net.ipv4.ip_forward The output of the command should indicate a value of 0. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*net.ipv4.ip_forward\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than net.ipv4.ip_forward = 0 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains net.ipv4.ip_forward = 0, and that one assignment is returned when $ grep -r net.ipv4.ip_forward /etc/sysctl.conf /etc/sysctl.d is executed. The ability to forward packets is only appropriate for routers. Is it the case that ? To set the runtime status of the net.ipv4.ip_forward kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.ip_forward=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.ip_forward = 0
RHEL-08-040260 sysctl_net_ipv4_ip_forward
V-230541 366 medium RHEL 8 must not accept router advertisements on all IPv6 interfaces. An illicit router advertisement message could result in a man-in-the-middle attack. The runtime status of the net.ipv6.conf.all.accept_ra kernel parameter can be queried by running the following command: $ sysctl net.ipv6.conf.all.accept_ra The output of the command should indicate a value of 0. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*net.ipv6.conf.all.accept_ra\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than net.ipv6.conf.all.accept_ra = 0 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains net.ipv6.conf.all.accept_ra = 0, and that one assignment is returned when $ grep -r net.ipv6.conf.all.accept_ra /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the net.ipv6.conf.all.accept_ra kernel parameter, run the following command:
$ sudo sysctl -w net.ipv6.conf.all.accept_ra=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv6.conf.all.accept_ra = 0
RHEL-08-040261 sysctl_net_ipv6_conf_all_accept_ra
V-230542 366 medium RHEL 8 must not accept router advertisements on all IPv6 interfaces by default. An illicit router advertisement message could result in a man-in-the-middle attack. The runtime status of the net.ipv6.conf.default.accept_ra kernel parameter can be queried by running the following command: $ sysctl net.ipv6.conf.default.accept_ra The output of the command should indicate a value of 0. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*net.ipv6.conf.default.accept_ra\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than net.ipv6.conf.default.accept_ra = 0 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains net.ipv6.conf.default.accept_ra = 0, and that one assignment is returned when $ grep -r net.ipv6.conf.default.accept_ra /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the net.ipv6.conf.default.accept_ra kernel parameter, run the following command:
$ sudo sysctl -w net.ipv6.conf.default.accept_ra=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv6.conf.default.accept_ra = 0
RHEL-08-040262 sysctl_net_ipv6_conf_default_accept_ra
V-230543 366 medium RHEL 8 must not allow interfaces to perform Internet Control Message Protocol (ICMP) redirects by default. ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages contain information from the system's route table possibly revealing portions of the network topology.
The ability to send ICMP redirects is only appropriate for systems acting as routers.
The runtime status of the net.ipv4.conf.default.send_redirects kernel parameter can be queried by running the following command: $ sysctl net.ipv4.conf.default.send_redirects The output of the command should indicate a value of 0. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*net.ipv4.conf.default.send_redirects\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than net.ipv4.conf.default.send_redirects = 0 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains net.ipv4.conf.default.send_redirects = 0, and that one assignment is returned when $ grep -r net.ipv4.conf.default.send_redirects /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the net.ipv4.conf.default.send_redirects kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.conf.default.send_redirects=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.conf.default.send_redirects = 0
RHEL-08-040270 sysctl_net_ipv4_conf_default_send_redirects
V-244553 366 medium RHEL 8 must ignore IPv4 Internet Control Message Protocol (ICMP) redirect messages. ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages modify the host's route table and are unauthenticated. An illicit ICMP redirect message could result in a man-in-the-middle attack.
This feature of the IPv4 protocol has few legitimate uses. It should be disabled unless absolutely required."
The runtime status of the net.ipv4.conf.all.accept_redirects kernel parameter can be queried by running the following command: $ sysctl net.ipv4.conf.all.accept_redirects The output of the command should indicate a value of 0. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*net.ipv4.conf.all.accept_redirects\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than net.ipv4.conf.all.accept_redirects = 0 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains net.ipv4.conf.all.accept_redirects = 0, and that one assignment is returned when $ grep -r net.ipv4.conf.all.accept_redirects /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the net.ipv4.conf.all.accept_redirects kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.conf.all.accept_redirects=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.conf.all.accept_redirects = 0
RHEL-08-040279 sysctl_net_ipv4_conf_all_accept_redirects
V-230544 366 medium RHEL 8 must ignore IPv6 Internet Control Message Protocol (ICMP) redirect messages. An illicit ICMP redirect message could result in a man-in-the-middle attack. The runtime status of the net.ipv6.conf.all.accept_redirects kernel parameter can be queried by running the following command: $ sysctl net.ipv6.conf.all.accept_redirects The output of the command should indicate a value of 0. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*net.ipv6.conf.all.accept_redirects\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than net.ipv6.conf.all.accept_redirects = 0 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains net.ipv6.conf.all.accept_redirects = 0, and that one assignment is returned when $ grep -r net.ipv6.conf.all.accept_redirects /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the net.ipv6.conf.all.accept_redirects kernel parameter, run the following command:
$ sudo sysctl -w net.ipv6.conf.all.accept_redirects=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv6.conf.all.accept_redirects = 0
RHEL-08-040280 sysctl_net_ipv6_conf_all_accept_redirects
V-230545 366 medium RHEL 8 must disable access to network bpf syscall from unprivileged processes. Loading and accessing the packet filters programs and maps using the bpf() syscall has the potential of revealing sensitive information about the kernel state. The runtime status of the kernel.unprivileged_bpf_disabled kernel parameter can be queried by running the following command: $ sysctl kernel.unprivileged_bpf_disabled The output of the command should indicate a value of 1. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*kernel.unprivileged_bpf_disabled\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than kernel.unprivileged_bpf_disabled = 1 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains kernel.unprivileged_bpf_disabled = 1, and that one assignment is returned when $ grep -r kernel.unprivileged_bpf_disabled /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the kernel.unprivileged_bpf_disabled kernel parameter, run the following command:
$ sudo sysctl -w kernel.unprivileged_bpf_disabled=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
kernel.unprivileged_bpf_disabled = 1
RHEL-08-040281 sysctl_kernel_unprivileged_bpf_disabled
V-230546 366 medium RHEL 8 must restrict usage of ptrace to descendant processes. Unrestricted usage of ptrace allows compromised binaries to run ptrace on another processes of the user. Like this, the attacker can steal sensitive information from the target processes (e.g. SSH sessions, web browser, ...) without any additional assistance from the user (i.e. without resorting to phishing). The runtime status of the kernel.yama.ptrace_scope kernel parameter can be queried by running the following command: $ sysctl kernel.yama.ptrace_scope The output of the command should indicate a value of 1. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*kernel.yama.ptrace_scope\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than kernel.yama.ptrace_scope = 1 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains kernel.yama.ptrace_scope = 1, and that one assignment is returned when $ grep -r kernel.yama.ptrace_scope /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the kernel.yama.ptrace_scope kernel parameter, run the following command:
$ sudo sysctl -w kernel.yama.ptrace_scope=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
kernel.yama.ptrace_scope = 1
RHEL-08-040282 sysctl_kernel_yama_ptrace_scope
V-230547 366 medium RHEL 8 must restrict exposed kernel pointer addresses access. Exposing kernel pointers (through procfs or seq_printf()) exposes kernel writeable structures that can contain functions pointers. If a write vulnereability occurs in the kernel allowing a write access to any of this structure, the kernel can be compromise. This option disallow any program withtout the CAP_SYSLOG capability from getting the kernel pointers addresses, replacing them with 0. The runtime status of the kernel.kptr_restrict kernel parameter can be queried by running the following command: $ sysctl kernel.kptr_restrict The output of the command should indicate a value of 1. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*kernel.kptr_restrict\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than kernel.kptr_restrict = 1 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains kernel.kptr_restrict = 1, and that one assignment is returned when $ grep -r kernel.kptr_restrict /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the kernel.kptr_restrict kernel parameter, run the following command:
$ sudo sysctl -w kernel.kptr_restrict=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
kernel.kptr_restrict = 1
RHEL-08-040283 sysctl_kernel_kptr_restrict
V-230548 366 medium RHEL 8 must disable the use of user namespaces. User namespaces are used primarily for Linux containers. The value 0 disallows the use of user namespaces. The runtime status of the user.max_user_namespaces kernel parameter can be queried by running the following command: $ sysctl user.max_user_namespaces The output of the command should indicate a value of 0. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*user.max_user_namespaces\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than user.max_user_namespaces = 0 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains user.max_user_namespaces = 0, and that one assignment is returned when $ grep -r user.max_user_namespaces /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the user.max_user_namespaces kernel parameter, run the following command:
$ sudo sysctl -w user.max_user_namespaces=0
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
user.max_user_namespaces = 0
When containers are deployed on the machine, the value should be set to large non-zero value.
RHEL-08-040284 sysctl_user_max_user_namespaces
V-230549 366 medium RHEL 8 must use reverse path filtering on all IPv4 interfaces. Enabling reverse path filtering drops packets with source addresses that should not have been able to be received on the interface they were received on. It should not be used on systems which are routers for complicated networks, but is helpful for end hosts and routers serving small networks. The runtime status of the net.ipv4.conf.all.rp_filter kernel parameter can be queried by running the following command: $ sysctl net.ipv4.conf.all.rp_filter The output of the command should indicate a value of 1. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*net.ipv4.conf.all.rp_filter\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than net.ipv4.conf.all.rp_filter = 1 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains net.ipv4.conf.all.rp_filter = 1, and that one assignment is returned when $ grep -r net.ipv4.conf.all.rp_filter /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the net.ipv4.conf.all.rp_filter kernel parameter, run the following command:
$ sudo sysctl -w net.ipv4.conf.all.rp_filter=1
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.ipv4.conf.all.rp_filter = 1
RHEL-08-040285 sysctl_net_ipv4_conf_all_rp_filter
V-244554 366 medium RHEL 8 must enable hardening for the Berkeley Packet Filter Just-in-time compiler. When hardened, the extended Berkeley Packet Filter just-in-time compiler will randomize any kernel addresses in the BPF programs and maps, and will not expose the JIT addresses in /proc/kallsyms. The runtime status of the net.core.bpf_jit_harden kernel parameter can be queried by running the following command: $ sysctl net.core.bpf_jit_harden The output of the command should indicate a value of 2. The preferable way how to assure the runtime compliance is to have correct persistent configuration, and rebooting the system. The persistent kernel parameter configuration is performed by specifying the appropriate assignment in any file located in the /etc/sysctl.d directory. Verify that there is not any existing incorrect configuration by executing the following command: $ grep -r '^\s*net.core.bpf_jit_harden\s*=' /etc/sysctl.conf /etc/sysctl.d If any assignments other than net.core.bpf_jit_harden = 2 are found, or the correct assignment is duplicated, remove those offending lines from respective files, and make sure that exactly one file in /etc/sysctl.d contains net.core.bpf_jit_harden = 2, and that one assignment is returned when $ grep -r net.core.bpf_jit_harden /etc/sysctl.conf /etc/sysctl.d is executed. Is it the case that the correct value is not returned? To set the runtime status of the net.core.bpf_jit_harden kernel parameter, run the following command:
$ sudo sysctl -w net.core.bpf_jit_harden=2
To make sure that the setting is persistent, add the following line to a file in the directory /etc/sysctl.d:
net.core.bpf_jit_harden = 2
RHEL-08-040286 sysctl_net_core_bpf_jit_harden
V-230550 366 medium RHEL 8 must be configured to prevent unrestricted mail relaying. If unrestricted mail relaying is permitted, unauthorized senders could use this host as a mail relay for the purpose of sending spam or other unauthorized activity. To verify the system is configured to prevent unrestricted mail relaying, run the following command: $ sudo postconf -n smtpd_client_restrictions The output should return: smtpd_client_restrictions = permit_mynetworks,reject Is it the case that it is not? Modify the
/etc/postfix/main.cf
file to restrict client connections to the local network with the following command:
$ sudo postconf -e 'smtpd_client_restrictions = permit_mynetworks,reject'
RHEL-08-040290 postfix_prevent_unrestricted_relay
V-230551 366 low The RHEL 8 file integrity tool must be configured to verify extended attributes. Extended attributes in file systems are used to contain arbitrary data and file metadata with security implications. To determine that AIDE is verifying extended file attributes, run the following command: $ grep xattrs /etc/aide.conf Verify that the xattrs option is added to the correct ruleset. Is it the case that the xattrs option is missing or not added to the correct ruleset? By default, the xattrs option is added to the FIPSR ruleset in AIDE. If using a custom ruleset or the xattrs option is missing, add xattrs to the appropriate ruleset. For example, add xattrs to the following line in /etc/aide.conf:
FIPSR = p+i+n+u+g+s+m+c+acl+selinux+xattrs+sha256
AIDE rules can be configured in multiple ways; this is merely one example that is already configured by default. The remediation provided with this rule adds xattrs to all rule sets available in /etc/aide.conf
RHEL-08-040300 aide_verify_ext_attributes
V-230552 366 low The RHEL 8 file integrity tool must be configured to verify Access Control Lists (ACLs). ACLs can provide permissions beyond those permitted through the file mode and must be verified by the file integrity tools. To determine that AIDE is verifying ACLs, run the following command: $ grep acl /etc/aide.conf Verify that the acl option is added to the correct ruleset. Is it the case that the acl option is missing or not added to the correct ruleset? By default, the acl option is added to the FIPSR ruleset in AIDE. If using a custom ruleset or the acl option is missing, add acl to the appropriate ruleset. For example, add acl to the following line in /etc/aide.conf:
FIPSR = p+i+n+u+g+s+m+c+acl+selinux+xattrs+sha256
AIDE rules can be configured in multiple ways; this is merely one example that is already configured by default. The remediation provided with this rule adds acl to all rule sets available in /etc/aide.conf
RHEL-08-040310 aide_verify_acls
V-230553 366 medium The graphical display manager must not be installed on RHEL 8 unless approved. Unnecessary service packages must not be installed to decrease the attack surface of the system. X windows has a long history of security vulnerabilities and should not be installed unless approved and documented. To ensure the X Windows package group is removed, run the following command: $ rpm -qi xorg-x11-server-Xorg xorg-x11-server-common xorg-x11-server-utils xorg-x11-server-Xwayland For each package mentioned above you should receive following line: package <package> is not installed Is it the case that xorg related packages are not removed and run level is not correctly configured? By removing the following packages, the system no longer has X Windows installed. xorg-x11-server-Xorg xorg-x11-server-common xorg-x11-server-utils xorg-x11-server-Xwayland If X Windows is not installed then the system cannot boot into graphical user mode. This prevents the system from being accidentally or maliciously booted into a graphical.target mode. To do so, run the following command:
sudo yum remove xorg-x11-server-Xorg xorg-x11-server-common xorg-x11-server-utils xorg-x11-server-Xwayland
Additionally, setting the system's default target to multi-user.target will prevent automatic startup of the X server. To do so, run:
$ systemctl set-default multi-user.target
You should see the following output:
Removed symlink /etc/systemd/system/default.target.
Created symlink from /etc/systemd/system/default.target to /usr/lib/systemd/system/multi-user.target.
RHEL-08-040320 xwindows_remove_packages
V-230554 366 medium RHEL 8 network interfaces must not be in promiscuous mode. Network interfaces in promiscuous mode allow for the capture of all network traffic visible to the system. If unauthorized individuals can access these applications, it may allow them to collect information such as logon IDs, passwords, and key exchanges between systems.

If the system is being used to perform a network troubleshooting function, the use of these tools must be documented with the Information Systems Security Manager (ISSM) and restricted to only authorized personnel.
To verify that Promiscuous mode of an interface is disabled, run the following command: $ ip link | grep PROMISC The output returned should not return any network device containing PROMISC. Is it the case that any network device is in promiscuous mode? The system should not be acting as a network sniffer, which can capture all traffic on the network to which it is connected. Run the following to determine if any interface is running in promiscuous mode:
$ ip link | grep PROMISC
Promiscuous mode of an interface can be disabled with the following command:
$ sudo ip link set dev device_name multicast off promisc off
RHEL-08-040330 network_sniffer_disabled
V-230555 366 medium RHEL 8 remote X connections for interactive users must be disabled unless to fulfill documented and validated mission requirements. Disable X11 forwarding unless there is an operational requirement to use X11 applications directly. There is a small risk that the remote X11 servers of users who are logged in via SSH with X11 forwarding could be compromised by other users on the X11 server. Note that even if X11 forwarding is disabled, users can always install their own forwarders. To determine how the SSH daemon's X11Forwarding option is set, run the following command: $ sudo grep -i X11Forwarding /etc/ssh/sshd_config If no line, a commented line, or a line indicating the value no is returned, then the required value is set. Is it the case that the required value is not set? The X11Forwarding parameter provides the ability to tunnel X11 traffic through the connection to enable remote graphic connections. SSH has the capability to encrypt remote X11 connections when SSH's X11Forwarding option is enabled.

To disable X11 Forwarding, add or correct the following line in /etc/ssh/sshd_config:
X11Forwarding no
RHEL-08-040340 sshd_disable_x11_forwarding
V-230556 366 medium The RHEL 8 SSH daemon must prevent remote hosts from connecting to the proxy display. When X11 forwarding is enabled, there may be additional exposure to the server and client displays if the sshd proxy display is configured to listen on the wildcard address. By default, sshd binds the forwarding server to the loopback address and sets the hostname part of the DISPLAY environment variable to localhost. This prevents remote hosts from connecting to the proxy display. To determine how the SSH daemon's X11UseLocalhost option is set, run the following command: $ sudo grep -i X11UseLocalhost /etc/ssh/sshd_config If no line, a commented line, or a line indicating the value yes is returned, then the required value is set. Is it the case that the display proxy is listening on wildcard address? The SSH daemon should prevent remote hosts from connecting to the proxy display. Make sure that the option X11UseLocalhost is set to yes within the SSH server configuration file. RHEL-08-040341 sshd_x11_use_localhost
V-230557 366 medium If the Trivial File Transfer Protocol (TFTP) server is required, the RHEL 8 TFTP daemon must be configured to operate in secure mode. Using the -s option causes the TFTP service to only serve files from the given directory. Serving files from an intentionally-specified directory reduces the risk of sharing files which should remain private. If TFTP is not installed, this is not applicable. To determine if TFTP is installed, run the following command: $ rpm -qa | grep tftp Verify tftp is configured by with the -s option by running the following command: grep "server_args" /etc/xinetd.d/tftp The output should indicate the server_args variable is configured with the -s flag, matching the example below: $ grep "server_args" /etc/xinetd.d/tftp server_args = -s Is it the case that this flag is missing? If running the tftp service is necessary, it should be configured to change its root directory at startup. To do so, ensure /etc/xinetd.d/tftp includes -s as a command line argument, as shown in the following example:
server_args = -s 
RHEL-08-040350 tftpd_uses_secure_mode
V-230558 366 high A File Transfer Protocol (FTP) server package must not be installed unless mission essential on RHEL 8. Removing the vsftpd package decreases the risk of its accidental activation. Run the following command to determine if the vsftpd package is installed: $ rpm -q vsftpd Is it the case that the package is installed? The vsftpd package can be removed with the following command:
 $ sudo yum erase vsftpd
RHEL-08-040360 package_vsftpd_removed
V-230559 381 medium The gssproxy package must not be installed unless mission essential on RHEL 8. gssproxy is a proxy for GSS API credential handling. Run the following command to determine if the gssproxy package is installed: $ rpm -q gssproxy Is it the case that the package is installed? The gssproxy package can be removed with the following command:
$ sudo yum erase gssproxy
RHEL-08-040370 package_gssproxy_removed
V-230560 366 medium The iprutils package must not be installed unless mission essential on RHEL 8. iprutils provides a suite of utlilities to manage and configure SCSI devices supported by the ipr SCSI storage device driver. Run the following command to determine if the iprutils package is installed: $ rpm -q iprutils Is it the case that the package is installed? The iprutils package can be removed with the following command:
$ sudo yum erase iprutils
RHEL-08-040380 package_iprutils_removed
V-230561 366 medium The tuned package must not be installed unless mission essential on RHEL 8. tuned contains a daemon that tunes the system settings dynamically. It does so by monitoring the usage of several system components periodically. Based on that information, components will then be put into lower or higher power savings modes to adapt to the current usage. Run the following command to determine if the tuned package is installed: $ rpm -q tuned Is it the case that the package is installed? The tuned package can be removed with the following command:
$ sudo yum erase tuned
RHEL-08-040390 package_tuned_removed