STIGUI
V-270712CAT I — High severitySV-270712r1268251_rule

Ubuntu 24.04 LTS must disable the x86 Ctrl-Alt-Delete key sequence.

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

Discussion

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.

Check

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

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

Identifiers

Group ID
V-270712
Group title
SRG-OS-000480-GPOS-00227
Rule ID
SV-270712r1268251_rule
Check ID
C-74745r1068362_chk
Fix ID
F-74646r1067121_fix