Without the capability to generate audit records, it would be difficult to establish, correlate, and investigate the events relating to an incident, or identify those responsible for one. DoD has defined the list of events for which the operating system will provide an audit record generation capability as the following:
(i) Successful and unsuccessful attempts to access, modify, or delete privileges, security objects, security levels, or categories of information (e.g., classification levels);
(ii) Access actions, such as successful and unsuccessful logon attempts, privileged activities or other system level access, starting and ending time for user access to the system, concurrent logons from different workstations, successful and unsuccessful accesses to objects, all program initiations, and all direct access to the information system;
(iii) All account creations, modifications, disabling, and terminations; and
(iv) All kernel module load, unload, and restart actions.
The options to configure the audit daemon are located in the /etc/security/audit_control file. To view the current settings, run the following command:
sudo grep ^flags /etc/security/audit_control
If the 'lo', 'ad', and 'aa' options are not set, this is a finding.
To set the audit flags to the recommended setting, run the following command to add the flags 'lo', 'ad', and 'aa' all at once:
sudo sed -i.bak '/^flags/ s/$/,lo,ad,aa/' /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.