RHEL 9 SSH private host key files must have mode 0640 or less permissive.
Severity | Group ID | Group Title | Version | Rule ID | Date | STIG Version |
|---|---|---|---|---|---|---|
| medium | V-258000 | SRG-OS-000480-GPOS-00227 | RHEL-09-255120 | SV-258000r1045063_rule | 2025-02-27 | 2 |
| 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 "0640" or less permissive with the following command: $ stat -c "%a %n" /etc/ssh/*_key 640 /etc/ssh/ssh_host_dsa_key 640 /etc/ssh/ssh_host_ecdsa_key 640 /etc/ssh/ssh_host_ed25519_key 640 /etc/ssh/ssh_host_rsa_key If any private host key file has a mode more permissive than "0640", this is a finding. |
| ✔️ Fix |
|---|
| Configure the mode of SSH private host key files under "/etc/ssh" to "0640" with the following command: $ sudo chmod 0640 /etc/ssh/ssh_host*key Restart the SSH daemon for the changes to take effect: $ sudo systemctl restart sshd.service |