UCF STIG Viewer Logo

RHEL 8 must not allow users to override SSH environment variables.


Overview

Finding ID Version Rule ID IA Controls Severity
V-230330 RHEL-08-010830 SV-230330r646870_rule Medium
Description
SSH environment options potentially allow users to bypass access restriction in some configurations.
STIG Date
Red Hat Enterprise Linux 8 Security Technical Implementation Guide 2022-06-15

Details

Check Text ( C-32999r567736_chk )
Verify that unattended or automatic logon via ssh is disabled with the following command:

$ sudo grep -i PermitUserEnvironment /etc/ssh/sshd_config

PermitUserEnvironment no

If "PermitUserEnvironment" is set to "yes", is missing completely, or is commented out, this is a finding.
Fix Text (F-32974r567737_fix)
Configure RHEL 8 to allow the SSH daemon to not allow unattended or automatic logon to the system.

Add or edit the following line in the "/etc/ssh/sshd_config" file:

PermitUserEnvironment no

The SSH daemon must be restarted for the changes to take effect. To restart the SSH daemon, run the following command:

$ sudo systemctl restart sshd.service