The operating system must generate audit records for all kernel module load, unload, and restart actions, and also for all program initiations.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-58483	AOSX-09-002065	SV-72913r1_rule		Medium

Description
Kernel modules, called kernel extensions in Mac OS X, are compiled segments of code that are dynamically loaded into the kernel as required to support specific pieces of hardware or functionality. Privileged users are permitted to load or unload kernel extensions manually. An attacker might attempt to load a kernel extension that is known to be insecure to increase the attack surface of the system, or a user might plug in an unauthorized device that then triggers a kernel extension to be loaded. Auditing administrative actions, which include the loading or unloading of kernel extensions, mitigates this risk.

Description

Kernel modules, called kernel extensions in Mac OS X, are compiled segments of code that are dynamically loaded into the kernel as required to support specific pieces of hardware or functionality. Privileged users are permitted to load or unload kernel extensions manually. An attacker might attempt to load a kernel extension that is known to be insecure to increase the attack surface of the system, or a user might plug in an unauthorized device that then triggers a kernel extension to be loaded. Auditing administrative actions, which include the loading or unloading of kernel extensions, mitigates this risk.

STIG	Date
Apple OS X 10.9 (Mavericks) Workstation Security Technical Implementation Guide	2015-02-26

Details

Check Text ( C-59333r1_chk )
In order to view the currently configured flags for the audit daemon, run the following command: sudo grep ^flags /etc/security/audit_control Privileged access, including administrative use of the command line tools kextload and kextunload, is logged via the 'ad' flag. If 'ad' is not listed in the result of the check, this is a finding.

Fix Text (F-63821r1_fix)
To make sure the appropriate flags are enabled for auditing, run the following command: sudo sed -i.bak '/^flags/ s/$/,ad/' /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.