The x86 Ctrl-Alt-Delete key sequence must be disabled on TOSS 5.

A locally logged-in 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 operating system environment, this can create the risk of short-term loss of systems availability due to unintentional reboot.

In a graphical user environment, risk of unintentional reboot from the Ctrl-Alt-Delete sequence is reduced because the user will be prompted before any action is taken.

Verify TOSS 5 is not configured to reboot the system when Ctrl-Alt-Delete is pressed using 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 "ctrl-alt-del.target" is loaded and not masked, this is a finding.

Configure TOSS 5 to disable "ctrl-alt-del.target" using the following command:

$ sudo systemctl disable --now ctrl-alt-del.target
$ sudo systemctl mask --now ctrl-alt-del.target