Rule version UBTU-24-300026 · STIG v1 · 2026-09-09
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.
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.
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