TOSS 5 must disable the ability of a user to accidentally press Ctrl-Alt-Del and cause a system to shut down or reboot.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-282718 | TOSS-05-000281 | SV-282718r1201134_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-282718r1201134_chk)
Verify TOSS 5 is configured to ignore 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.
$ gsettings get org.gnome.settings-daemon.plugins.media-keys logout
"['']"
If the GNOME desktop is configured to shut down when Ctrl-Alt-Del is pressed, this is a finding.
Fix Text (F-87184r1201133_fix)
Configure TOSS 5 to ignore the Ctrl-Alt-Del sequence in the GNOME desktop.
Add or update the [org/gnome/settings-daemon/plugins/media-keys] section of the /etc/dconf/db/local.d/00-security-settings database file and add or update the following lines:
[org/gnome/settings-daemon/plugins/media-keys]
logout=['']
Run the following command to update the database:
$ sudo dconf update