Vulnerability Discussion

Reconstruction of harmful events or forensic analysis is not possible if audit records do not contain enough information.

At a minimum, the organization must audit the full-text recording of privileged access commands. The organization must maintain audit trails in sufficient detail to reconstruct events to determine the cause and impact of compromise.

Satisfies: SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215

Check

Verify the operating system generates audit records when successful/unsuccessful attempts to access the "/etc/sudoers" file and files in the "/etc/sudoers.d/" directory.

Check for modification of the following files being audited by performing the following commands to check the file system rules in "/etc/audit/audit.rules":

# grep -i "/etc/sudoers" /etc/audit/audit.rules

-w /etc/sudoers -p wa -k privileged-actions

# grep -i "/etc/sudoers.d/" /etc/audit/audit.rules

-w /etc/sudoers.d/ -p wa -k privileged-actions

If the commands do not return output that match the examples, this is a finding.

Fix

Configure the operating system to generate audit records when successful/unsuccessful attempts to access the "/etc/sudoers" file and files in the "/etc/sudoers.d/" directory.

Add or update the following rule in "/etc/audit/rules.d/audit.rules":

-w /etc/sudoers -p wa -k privileged-actions

-w /etc/sudoers.d/ -p wa -k privileged-actions

The audit daemon must be restarted for the changes to take effect.