UBTU-24-600200 - Ubuntu 24.04 LTS must configure the uncomplicated firewall to rate-limit impacted network interfaces.

Information

Denial of service (DoS) occurs when a resource is not available for legitimate users, resulting in the organization not being able to accomplish its mission or causing it to operate at degraded capacity.

This requirement addresses the configuration of Ubuntu 24.04 LTS to mitigate the impact of DoS attacks that have occurred or are ongoing on system availability. For each system, known and potential DoS attacks must be identified and solutions for each type implemented. A variety of technologies exist to limit or, in some cases, eliminate the effects of DoS attacks (e.g., limiting processes or establishing memory partitions). Employing increased capacity and bandwidth, combined with service redundancy, may reduce the susceptibility to some DoS attacks.

NOTE: Nessus has provided the target output to assist in reviewing the benchmark to ensure target compliance.

Solution

Configure the application firewall to protect against or limit the effects of DoS attacks by ensuring Ubuntu 24.04 LTS is implementing rate-limiting measures on impacted network interfaces.

To change the Status of ufw to "active" use the following command:
$ sudo ufw enable

Check all the services listening to the ports with the following command:

$ sudo ss -l46ut
Netid State Recv-Q Send-Q Local Address:Port Peer Address:Port Process
tcp LISTEN 0 128 [::]:ssh [::]:*

For each service with a port listening to connections, run the following command, replacing "[service]" with the service that needs to be rate limited.

$ sudo ufw limit [service]

Rate-limiting can also be done on an interface. An example of adding a rate-limit on the eth0 interface follows:

$ sudo ufw limit in on eth0

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_CAN_Ubuntu_24-04_LTS_V1R1_STIG.zip

Item Details

Category: SYSTEM AND COMMUNICATIONS PROTECTION

References: 800-53|SC-5, CAT|II, CCI|CCI-002385, Rule-ID|SV-270754r1066751_rule, STIG-ID|UBTU-24-600200, Vuln-ID|V-270754

Plugin: Unix

Control ID: c37513b9ab8a17e0a011ae673948a81cd050d611492e56f2c3137857e346fb2d