Ubuntu 24.04 LTS must disable the x86 Ctrl-Alt-Delete key sequence.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-270712 | UBTU-24-300026 | SV-270712r1068363_rule | CCI-000366 | high |
| Description | ||||
| A locally logged-on user who presses Ctrl-Alt-Delete, when at the console, can reboot the system. If accidentally pressed, as could happen in the case of a mixed OS environment, this can create the risk of short-term loss of availability of systems due to unintentional reboot. | ||||
| STIG | Date | |||
| Canonical Ubuntu 24.04 LTS Security Technical Implementation Guide | 2025-05-16 | |||
Details
Check Text (C-270712r1068363_chk)
Verify Ubuntu 24.04 LTS is not configured to reboot the system when Ctrl-Alt-Delete is pressed with the following command:
$ systemctl status ctrl-alt-del.target
o ctrl-alt-del.target
Loaded: masked (Reason: Unit ctrl-alt-del.target is masked.)
Active: inactive (dead)
If the "ctrl-alt-del.target" is not masked, this is a finding.
Fix Text (F-74646r1067121_fix)
Configure the system to disable the Ctrl-Alt-Delete sequence for the command line with the following commands:
$ sudo systemctl disable ctrl-alt-del.target
[...]
$ sudo systemctl mask ctrl-alt-del.target
Created symlink /etc/systemd/system/ctrl-alt-del.target ? /dev/null.
Reload the daemon to take effect:
$ sudo systemctl daemon-reload