The Ubuntu operating system must disable the x86 Ctrl-Alt-Delete key sequence.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-238380	UBTU-20-010460	SV-238380r832974_rule		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 20.04 LTS Security Technical Implementation Guide	2023-09-08

Details

Check Text ( C-41590r832972_chk )
Verify the Ubuntu operating system is not configured to reboot the system when Ctrl-Alt-Delete is pressed. Check that the "ctrl-alt-del.target" (otherwise also known as reboot.target) is not active with the following command: $ sudo systemctl status ctrl-alt-del.target 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.

Check Text ( C-41590r832972_chk )

Verify the Ubuntu operating system is not configured to reboot the system when Ctrl-Alt-Delete is pressed.

Check that the "ctrl-alt-del.target" (otherwise also known as reboot.target) is not active with the following command:

$ sudo systemctl status ctrl-alt-del.target
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-41549r832973_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 Reload the daemon to take effect: $ sudo systemctl daemon-reload