AlmaLinux OS 9 SSH private host key files must have mode 0640 or less permissive.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-269265 | ALMA-09-020920 | SV-269265r1050147_rule | Medium |
| Description |
| If an unauthorized user obtains the private SSH host key file, the host could be impersonated. |
| STIG | Date |
| CloudLinux AlmaLinux OS 9 Security Technical Implementation Guide | 2025-05-22 |
Details
| Check Text (C-73296r1048171_chk) |
| Verify the SSH private host key files have a mode of "0640" or less permissive with the following command: $ stat -c "%#a %n" /etc/ssh/ssh_host*key 0640 /etc/ssh/ssh_host_ecdsa_key 0640 /etc/ssh/ssh_host_rsa_key If any private host key file has a mode more permissive than "0640", this is a finding. |
| Fix Text (F-73197r1048172_fix) |
| Configure the mode of SSH private host key files under "/etc/ssh" to "0640" with the following command: $ chmod 0640 /etc/ssh/ssh_host*key Restart the SSH daemon for the changes to take effect: $ systemctl restart sshd.service |