The Photon operating system must configure Secure Shell (SSH) to disallow compression of the encrypted session stream.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-258878	PHTN-40-000215	SV-258878r933695_rule		Medium

Description
If compression is allowed in an SSH connection prior to authentication, vulnerabilities in the compression software could result in compromise of the system from an unauthenticated connection.

STIG	Date
VMware vSphere 8.0 vCenter Appliance Photon OS 4.0 Security Technical Implementation Guide	2023-10-29

Details

Check Text ( C-62618r933693_chk )
At the command line, run the following command to verify the running configuration of sshd: # sshd -T|&grep -i Compression Example result: compression no If there is no output or if "Compression" is not set to "delayed" or "no", this is a finding.

Fix Text (F-62527r933694_fix)
Navigate to and open: /etc/ssh/sshd_config Ensure the "Compression" line is uncommented and set to the following: Compression no At the command line, run the following command: # systemctl restart sshd.service