The operating system must generate audit records when successful/unsuccessful attempts to modify security levels occur.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-59797	AOSX-10-002075	SV-74227r1_rule		Medium

Description
The permissions on a file establish which users are permitted to access or modify it. An attacker may attempt to change the permissions on a file to prevent legitimate users from accessing it or to grant additional access to an account the attacker controls. Auditing successful and unsuccessful attempts to modify security objects such as file permissions mitigates this risk.

STIG	Date
Apple OS X 10.10 (Yosemite) Workstation Security Technical Implementation Guide	2017-04-06

Details

Check Text ( C-60553r1_chk )
In order to view the currently configured flags for the audit daemon, run the following command: sudo grep ^flags /etc/security/audit_control Changes to file permissions are logged by way of the 'fm' flag. If 'fm' is not listed in the result of the check, this is a finding.

Fix Text (F-65207r1_fix)
To make sure the appropriate flags are enabled for auditing, run the following command: sudo sed -i.bak '/^flags/ s/$/,fm/' /etc/security/audit_control; sudo audit -s A text editor may also be used to implement the required updates to the /etc/security/audit_control file.