RHEL-09-654270 RHEL 9 audit system must protect logon UIDs from unauthorized change.
All changes in this version
Maps to AU-9, AU-12 via CCI-000162, CCI-000163, CCI-000164, CCI-000172
Title
RHEL 9 audit system must protect logon UIDs from unauthorized change.
Control
Verify the audit system prevents unauthorized changes to logon UIDs with the following command: $ sudo grep -i immutable /etc/audit/audit.rules --loginuid-immutable If the "--loginuid-immutable" option is not returned in the "/etc/audit/audit.rules", or the line is commented out, this is a finding.
Discussion
If modification of login user identifiers (UIDs) is not prevented, they can be changed by nonprivileged users and make auditing complicated or impossible. Satisfies: SRG-OS-000462-GPOS-00206, SRG-OS-000475-GPOS-00220, SRG-OS-000057-GPOS-00027, SRG-OS-000058-GPOS-00028, SRG-OS-000059-GPOS-00029
Related controls
CCI-000162, CCI-000163, CCI-000164, CCI-000172
Fix
Configure RHEL 9 auditing to prevent modification of login UIDs once they are set by adding the following line to /etc/audit/rules.d/audit.rules: --loginuid-immutable The audit daemon must be restarted for the changes to take effect.