STIGQter: STIG Summary: Tri-Lab Operating System Stack (TOSS) 4 Security Technical Implementation Guide Version: 2 Release: 6 Benchmark Date: 01 Jul 2026:

The x86 Ctrl-Alt-Delete key sequence in TOSS must be disabled if a graphical user interface is installed.

DISA Rule

SV-252963r991589_rule

Vulnerability Number

V-252963

Group Title

SRG-OS-000480-GPOS-00227

Rule Version

TOSS-04-020240

Severity

CAT I

CCI(s)

CCI-000366 - Implement the security configuration settings.

Weight

Fix Recommendation

Configure the system to disable the Ctrl-Alt-Delete sequence when using a graphical user interface by creating or editing the /etc/dconf/db/local.d/00-disable-CAD file.

Add the setting to disable the Ctrl-Alt-Delete sequence for a graphical user interface:

[org/gnome/settings-daemon/plugins/media-keys]
logout=''

Note: The value above is set to two single quotations.

Then update the dconf settings:

$ sudo dconf update

Check Contents

Verify TOSS is not configured to reboot the system when Ctrl-Alt-Delete is pressed when using a graphical user interface with the following command:

Note: This requirement assumes the use of the TOSS default graphical user interface, Gnome Shell. If the system does not have any graphical user interface installed, this requirement is Not Applicable.

$ sudo grep logout /etc/dconf/db/local.d/*

logout=''

If the "logout" key is bound to an action, is commented out, or is missing, this is a finding.

Vulnerability Number

V-252963

Documentable

False

Rule Version

TOSS-04-020240

Severity Override Guidance

Check Content Reference

Target Key

5469