Title

Ubuntu OS must immediately notify the system administrator (SA) and information system security officer (ISSO) when the audit record storage volume reaches 25 percent remaining of the allocated capacity. (Cat III impact)

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 Content

Verify Ubuntu OS 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 Text

Configure Ubuntu OS 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.

Additional Identifiers

Rule ID: SV-275682r1148096_rule

Vulnerability ID: V-275682

Group Title: SRG-OS-000343-GPOS-00134

Expert Comments

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