STIG ID: RHEL-09-255085 | SRG: SRG-OS-000480-GPOS-00229 | Severity: medium | CCI: | Vulnerability Id: V-257993
SSH environment options potentially allow users to bypass access restriction in some configurations.
Configure the RHEL 9 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
Restart the SSH daemon for the setting to take effect:
$ sudo systemctl restart sshd.service
Verify that unattended or automatic logon via SSH is disabled with the following command:
$ sudo grep -ir permituserenvironment /etc/ssh/sshd_config /etc/ssh/sshd_config.d/*
PermitUserEnvironment no
If "PermitUserEnvironment" is set to "yes", is missing completely, or is commented out, this is a finding.
If the required value is not set, this is a finding.