The Photon operating system must configure Secure Shell (SSH) to disable X11 forwarding.

Overview

Finding IDVersionRule IDIA ControlsSeverity
V-258875PHTN-40-000212SV-258875r933686_ruleCCI-000366medium
Description
X11 is an older, insecure graphics forwarding protocol. It is not used by Photon and should be disabled as a general best practice to limit attack surface area and communication channels.
STIGDate
VMware vSphere 8.0 vCenter Appliance Photon OS 4.0 Security Technical Implementation Guide2023-10-29

Details

Check Text (C-258875r933686_chk)

At the command line, run the following command to verify the running configuration of sshd: # sshd -T|&grep -i X11Forwarding Example result: x11forwarding no If "X11Forwarding" is not set to "no", this is a finding.

Fix Text (F-62524r933685_fix)

Navigate to and open: /etc/ssh/sshd_config Ensure the "X11Forwarding" line is uncommented and set to the following: X11Forwarding no At the command line, run the following command: # systemctl restart sshd.service