Vulnerability Discussion

If security personnel are not notified immediately when storage volume reaches 25 percent remaining of the allocated capacity, they are unable to plan for audit record storage capacity expansion.

Check

Verify Ubuntu 22.04 LTS is configured to notify the SA and ISSO when the audit record storage volume reaches 25 percent remaining of the allocated capacity by using the following command:

$ sudo grep -i space_left /etc/audit/auditd.conf
space_left = 25%
space_left_action = email

If "space_left" is set to a value less than "25%", is commented out, or is missing, this is a finding.

If "space_left_action" is not set to "email", is commented out, or is missing, this is a finding.

Note: 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.

Fix

Configure Ubuntu 22.04 LTS to notify the SA and ISSO when the audit record storage volume reaches 25 percent remaining of the allocated capacity.

Add or modify the following lines in the "/etc/audit/auditd.conf " file:

space_left = 25%
space_left_action = email

Restart the "auditd" service for the changes to take effect:

$ sudo systemctl restart auditd.service

Note: If the "space_left_action" parameter is set to "exec", ensure the command being executed notifies the SA and ISSO.