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 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-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215, SRG-OS-000064-GPOS-00033, SRG-OS-000466-GPOS-00210, SRG-OS-000458-GPOS-00203

Check

Verify Amazon Linux 2023 is configured so that an audit event is generated for any successful/unsuccessful use of the "chage" command by performing the following command to check the file system rules in "/etc/audit/audit.rules":

$ sudo grep -w chage /etc/audit/audit.rules
-a always,exit -F path=/usr/bin/chage -F perm=x -F auid>=1000 -F auid!=unset -k privileged-chage

If the command does not return a line, or the line is commented out, this is a finding.

Fix

Configure Amazon Linux 2023 so that the audit service generates an audit event for any successful/unsuccessful uses of the "chage" command by adding or updating the following rule in the "/etc/audit/rules.d/audit.rules" file:

-a always,exit -F path=/usr/bin/chage -F perm=x -F auid>=1000 -F auid!=unset -k privileged-chage

To load the rules to the kernel immediately, use the following command:

$ sudo augenrules --load