| Verify the Ubuntu operating system notifies the SA and ISSO (at a minimum) when allocated audit record storage volume reaches 75% of the repository maximum audit record storage capacity with the following command: |
$ sudo grep ^space_left_action /etc/audit/auditd.conf
$ sudo grep ^space_left /etc/audit/auditd.conf
If the "space_left" parameter is missing, set to blanks, or set to a value less than 25% of the space free in the allocated audit record storage, this is a finding.
If the "space_left_action" parameter is missing or set to blanks, this is a finding.
If the "space_left_action" is set to "syslog", the system logs the event but does not generate a notification, and this is a finding.
If the "space_left_action" is set to "exec", the system executes a designated script. If this script informs the SA of the event, this is not a finding.
If the "space_left_action" is set to "email", check the value of the "action_mail_acct" parameter with the following command:
$ sudo grep ^action_mail_acct /etc/audit/auditd.conf
The "action_mail_acct" parameter, if missing, defaults to "root". If the "action_mail_acct parameter" is not set to the email address of the SA(s) and/or ISSO, this is a finding.
Note: If the email address of the System Administrator
is on a remote system, a mail package must be available.