AlmaLinux OS 9 SSH private host key files must have mode 0600 or less permissive.

Severity
Group ID
Group Title
Version
Rule ID
Date
STIG Version
mediumV-269265SRG-OS-000480-GPOS-00227ALMA-09-020920SV-269265r1208312_rule2026-05-221

Description

If an unauthorized user obtains the private SSH host key file, the host could be impersonated.

ℹ️ Check

Verify the SSH private host key files have a mode of "0600" or less permissive with the following command: $ stat -c "%#a %n" /etc/ssh/ssh_host*key 0600 /etc/ssh/ssh_host_ecdsa_key 0600 /etc/ssh/ssh_host_rsa_key If any private host key file has a mode more permissive than "0600", this is a finding.

✔️ Fix

Configure the mode of SSH private host key files under "/etc/ssh" to "0600" with the following command: $ chmod 0600 /etc/ssh/ssh_host*key Restart the SSH daemon for the changes to take effect: $ systemctl restart sshd.service