TOSS 5 must prevent a user from overriding the Ctrl-Alt-Del sequence settings for the graphical user interface.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-282719 | TOSS-05-000282 | SV-282719r1201137_rule | CCI-000366 | medium |
| Description | ||||
| A locally logged-in user who presses Ctrl-Alt-Del, when at the console, can reboot the system. If accidentally pressed, as could happen in the case of mixed OS environment, this can create the risk of short-term loss of availability of systems due to unintentional reboot. | ||||
| STIG | Date | |||
| Tri-Lab Operating System Stack (TOSS) 5 Security Technical Implementation Guide | 2026-04-01 | |||
Details
Check Text (C-282719r1201137_chk)
Verify users cannot enable the Ctrl-Alt-Del sequence in the GNOME desktop using the following command:
Note: This requirement assumes the use of the TOSS 5 default graphical user interface, the GNOME desktop environment. If the system does not have any graphical user interface installed, this requirement is not applicable.
$ grep logout /etc/dconf/db/local.d/locks/*
/org/gnome/settings-daemon/plugins/media-keys/logout
If the output is not "/org/gnome/settings-daemon/plugins/media-keys/logout", the line is commented out, or the line is missing, this is a finding.
Fix Text (F-87185r1201136_fix)
Configure TOSS 5 to disallow the user changing the Ctrl-Alt-Del sequence in the GNOME desktop.
Create a database to container systemwide graphical user logon settings (if it does not already exist) using the following command:
$ sudo touch /etc/dconf/db/local.d/locks/session
Add the following line to the session locks file to prevent nonprivileged users from modifying the Ctrl-Alt-Del setting:
/org/gnome/settings-daemon/plugins/media-keys/logout
Run the following command to update the database:
$ sudo dconf update