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V-260516

CAT II (Medium)

Ubuntu 22.04 LTS must have an application firewall enabled.

Rule ID

SV-260516r1184061_rule

STIG

Canonical Ubuntu 22.04 LTS Security Technical Implementation Guide

Version

V2R8

CCIs

CCI-000366

Discussion

Firewalls protect computers from network attacks by blocking or limiting access to open network ports. Application firewalls limit which applications are allowed to communicate over the network.

Check Content

Verify the ufw is enabled on the system with the following command: 
 
    $ sudo ufw status
    Status: active
 
If the above command returns the status as "inactive" or any type of error, this is a finding. 

If the ufw is not installed, ask the system administrator if another application firewall is installed. If a different firewall is active on the system, this is not a finding.

Fix Text

Enable the ufw by using the following command: 
 
    $ sudo ufw enable

Note: Enabling the firewall will potentially disrupt ssh sessions.