The systemd Ctrl-Alt-Delete burst key sequence in TOSS must be disabled.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-252938 | TOSS-04-010360 | SV-252938r1155810_rule | CCI-000366 | 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. 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. | ||||
| STIG | Date | |||
| Tri-Lab Operating System Stack (TOSS) 4 Security Technical Implementation Guide | 2026-02-19 | |||
Details
Check Text (C-252938r1155810_chk)
Verify TOSS is configured to not reboot the system when Ctrl-Alt-Delete is pressed seven times within two seconds with the following command:
$ sudo grep -iR CtrlAltDelBurstAction /etc/systemd/system*
/etc/systemd/system.conf.d/55-CtrlAltDel-BurstAction:CtrlAltDelBurstAction=none
If the "CtrlAltDelBurstAction" is not set to "none", commented out, or is missing, this is a finding.
Fix Text (F-56341r1155809_fix)
Configure TOSS to disable the CtrlAltDelBurstAction by adding it to a drop file in a "/etc/systemd/system.conf.d/" configuration file:
If no drop file exists, create one with the following command:
$ sudo mkdir -p /etc/systemd/system.conf.d && sudo vi /etc/systemd/system.conf.d/55-CtrlAltDel-BurstAction
Edit the file to contain the setting by adding the following text:
CtrlAltDelBurstAction=none
Reload the daemon for this change to take effect.
$ sudo systemctl daemon-reload