AlmaLinux OS 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-269265 | SRG-OS-000480-GPOS-00227 | ALMA-09-020920 | SV-269265r1050147_rule | 2026-02-27 | 1 |
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/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
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