SLEM 5 SSH daemon private host key files must have mode 640 or less permissive.
Severity | Group ID | Group Title | Version | Rule ID | Date | STIG Version |
|---|---|---|---|---|---|---|
| medium | V-261294 | SRG-OS-000480-GPOS-00227 | SLEM-05-232045 | SV-261294r996359_rule | 2026-02-10 | 1 |
Description
If an unauthorized user obtains the private SSH host key file, the host could be impersonated.
ℹ️ Check
Verify SLEM 5 SSH daemon private host key files have mode "640" or less permissive.
The following command will find all SSH private key files on the system with the following command:
> sudo find / -name '*ssh_host*key' -exec ls -lL {} \;
Check the mode of the private host key files under "/etc/ssh" file with the following command:
> find /etc/ssh -name 'ssh_host*key' -exec stat -c "%a %n" {} \;
640 /etc/ssh/ssh_host_rsa_key
640 /etc/ssh/ssh_host_dsa_key
640 /etc/ssh/ssh_host_ecdsa_key
640 /etc/ssh/ssh_host_ed25519_key
If any file has a mode more permissive than "640", this is a finding.
✔️ Fix
Configure the mode of SLEM 5 SSH daemon private host key files under "/etc/ssh" to "640" with the following command:
> sudo chmod 640 /etc/ssh/ssh_host*key