The operating system must audit the enforcement actions used to restrict access associated with changes to the system.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-58505	AOSX-09-002110	SV-72935r1_rule		Medium

Description
By auditing access restriction enforcement, changes to application and OS configuration files can be audited. Without auditing the enforcement of access restrictions, it will be difficult to identify attempted attacks and an audit trail will not be available for forensic investigation. Enforcement actions are the methods or mechanisms used to prevent unauthorized changes to configuration settings. Enforcement action methods may be as simple as denying access to a file based on the application of file permissions (access restriction). Audit items may consist of lists of actions blocked by access restrictions or changes identified after the fact.

Description

By auditing access restriction enforcement, changes to application and OS configuration files can be audited. Without auditing the enforcement of access restrictions, it will be difficult to identify attempted attacks and an audit trail will not be available for forensic investigation. Enforcement actions are the methods or mechanisms used to prevent unauthorized changes to configuration settings. Enforcement action methods may be as simple as denying access to a file based on the application of file permissions (access restriction). Audit items may consist of lists of actions blocked by access restrictions or changes identified after the fact.

STIG	Date
Apple OS X 10.9 (Mavericks) Workstation Security Technical Implementation Guide	2017-01-05

Details

Check Text ( C-59355r1_chk )
In order to view the currently configured flags for the audit daemon, run the following command: sudo grep ^flags /etc/security/audit_control Enforcement actions are logged by way of the 'fm' flag, which audits permission changes, and '-fr' and '-fw', which denote failed attempts to read or write to a file. If 'fm', '-fr', and '-fw' are not listed in the result of the check, this is a finding.

Fix Text (F-63843r1_fix)
To make sure the appropriate flags are enabled for auditing, run the following command to add 'fm', '-fr', and '-fw' at the same time: sudo sed -i.bak '/^flags/ s/$/,fm,-fr,-fw/' /etc/security/audit_control; sudo audit -s A text editor may also be used to implement the required update to the /etc/security/audit_control file.