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V-269140

CAT I (High)

The systemd Ctrl-Alt-Delete burst key sequence in AlmaLinux OS 9 must be disabled.

Rule ID

SV-269140r1050022_rule

STIG

Cloud Linux AlmaLinux OS 9 Security Technical Implementation Guide

Version

V1R6

CCIs

CCI-002235

Discussion

A locally logged-on user who presses Ctrl-Alt-Delete in quick succession 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.

Check Content

Verify AlmaLinux OS 9 is configured to not reboot the system when Ctrl-Alt-Delete is pressed seven times within two seconds with the following command:

$ systemd-analyze cat-config systemd/system.conf | grep -v '#' | grep CtrlAltDel

CtrlAltDelBurstAction=none

If "CtrlAltDelBurstAction" is not set to "none", is commented out, or is missing, this is a finding.

Fix Text

Configure the system to disable the CtrlAltDelBurstAction by added or modifying the following line in the "/etc/systemd/system.conf" configuration file:

CtrlAltDelBurstAction=none

Reload the daemon for this change to take effect.

$ systemctl daemon-reexec