5.2.3.14 Ensure events that modify the system's Mandatory Access Controls are collected

Information

Monitor AppArmor, an implementation of mandatory access controls. The parameters below monitor any write access (potential additional, deletion or modification of files in the directory) or attribute changes to the /etc/apparmor/ and /etc/apparmor.d/ directories.

Note: If a different Mandatory Access Control method is used, changes to the corresponding directories should be audited.

Changes to files in the /etc/apparmor/ and /etc/apparmor.d/ directories could indicate that an unauthorized user is attempting to modify access controls and change security contexts, leading to a compromise of the system.

Solution

Edit or create a file in the /etc/audit/rules.d/ directory, ending inrules extension, with the relevant rules to monitor events that modify the system's Mandatory Access Controls.

Example:

# printf "
-w /etc/apparmor/ -p wa -k MAC-policy
-w /etc/apparmor.d/ -p wa -k MAC-policy
" >> /etc/audit/rules.d/50-MAC-policy.rules

Merge and load the rules into active configuration:

# augenrules --load

Check if reboot is required.

# if [[ $(auditctl -s | grep "enabled") =~ "2" ]]; then printf "Reboot required to load rules
"; fi

See Also

https://workbench.cisecurity.org/benchmarks/15023