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V-257786

CAT II (Medium)

RHEL 9 debug-shell systemd service must be disabled.

Rule ID

SV-257786r1044834_rule

STIG

Red Hat Enterprise Linux 9 Security Technical Implementation Guide

Version

V2R8

CCIs

CCI-002235

Discussion

The debug-shell requires no authentication and provides root privileges to anyone who has physical access to the machine. While this feature is disabled by default, masking it adds an additional layer of assurance that it will not be enabled via a dependency in systemd. This also prevents attackers with physical access from trivially bypassing security on the machine through valid troubleshooting configurations and gaining root access when the system is rebooted. Satisfies: SRG-OS-000324-GPOS-00125, SRG-OS-000480-GPOS-00227

Check Content

Verify RHEL 9 is configured to mask the debug-shell systemd service with the following command:

$ sudo systemctl status debug-shell.service

debug-shell.service
Loaded: masked (Reason: Unit debug-shell.service is masked.)
Active: inactive (dead)

If the "debug-shell.service" is loaded and not masked, this is a finding.

Fix Text

Configure RHEL 9 to mask the debug-shell systemd service with the following command:

$ sudo systemctl disable --now debug-shell.service
$ sudo systemctl mask --now debug-shell.service