The Photon operating system must be configured to protect the SSH public host key from unauthorized modification.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-239186	PHTN-67-000115	SV-239186r675366_rule		Medium

Description
If a public host key file is modified by an unauthorized user, the SSH service may be compromised.

STIG	Date
VMware vSphere 6.7 Photon OS Security Technical Implementation Guide	2021-04-15

Details

Check Text ( C-42397r675364_chk )
At the command line, execute the following command: # stat -c "%n permissions are %a and owned by %U:%G" /etc/ssh/*key.pub Expected result: /etc/ssh/ssh_host_dsa_key.pub permissions are 644 and owned by root:root /etc/ssh/ssh_host_ecdsa_key.pub permissions are 644 and owned by root:root /etc/ssh/ssh_host_ed25519_key.pub permissions are 644 and owned by root:root /etc/ssh/ssh_host_rsa_key.pub permissions are 644 and owned by root:root If the output does not match the expected result, this is a finding.

Check Text ( C-42397r675364_chk )

At the command line, execute the following command:

# stat -c "%n permissions are %a and owned by %U:%G" /etc/ssh/*key.pub

Expected result:

/etc/ssh/ssh_host_dsa_key.pub permissions are 644 and owned by root:root
/etc/ssh/ssh_host_ecdsa_key.pub permissions are 644 and owned by root:root
/etc/ssh/ssh_host_ed25519_key.pub permissions are 644 and owned by root:root
/etc/ssh/ssh_host_rsa_key.pub permissions are 644 and owned by root:root

If the output does not match the expected result, this is a finding.

Fix Text (F-42356r675365_fix)
At the command line, execute the following commands for each returned file: # chmod 644 # chown root:root