RHEL-09-211045 - The systemd Ctrl-Alt-Delete burst key sequence in RHEL 9 must be disabled.

Information

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.

Satisfies: SRG-OS-000324-GPOS-00125, SRG-OS-000480-GPOS-00227

Solution

Configure RHEL 9 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

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_RHEL_9_V2R7_STIG.zip

Item Details

Category: ACCESS CONTROL

References: 800-53|AC-6(10), CAT|I, CCI|CCI-002235, Rule-ID|SV-257784r1155651_rule, STIG-ID|RHEL-09-211045, Vuln-ID|V-257784

Plugin: Unix

Control ID: 21589c932bf9d3d69044d57c349959cecbcf393d27cecc4f6c775d1521e531e0