SLEM 5 SSH daemon must be configured to not allow authentication using known hosts authentication.
Severity | Group ID | Group Title | Version | Rule ID | Date | STIG Version |
|---|---|---|---|---|---|---|
| medium | V-261340 | SRG-OS-000480-GPOS-00227 | SLEM-05-255075 | SV-261340r996483_rule | 2026-02-10 | 1 |
Description
Configuring this setting for the SSH daemon provides additional assurance that remote logon via SSH will require a password, even in the event of misconfiguration elsewhere.
ℹ️ Check
Verify SLEM 5 SSH daemon is configured to not allow authentication using "known hosts" authentication with the following command:
> sudo /usr/sbin/sshd -dd 2>&1 | awk '/filename/ {print $4}' | tr -d '\r' | tr '\n' ' ' | xargs sudo grep -iH '^\s*ignoreuserknownhosts'
/etc/ssh/sshd_config:IgnoreUserKnownHosts yes
If "IgnoreUserKnownHosts" is not set to "no", is commented out, missing, or conflicting results are returned, this is a finding.
✔️ Fix
Configure SLEM 5 SSH daemon to not allow authentication using "known hosts" authentication.
Add or modify the following line in the "/etc/ssh/sshd_config" file:
IgnoreUserKnownHosts yes
Restart the SSH daemon in order for the changes to take effect:
> sudo systemctl restart sshd.service