The TOSS SSH daemon must not allow authentication using known host's authentication.

Severity
Group ID
Group Title
Version
Rule ID
Date
STIG Version
mediumV-252942SRG-OS-000480-GPOS-00227TOSS-04-010400SV-252942r991589_rule2024-05-302
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 the SSH daemon does not allow authentication using known host's authentication with the following command: $ sudo grep -i IgnoreUserKnownHosts /etc/ssh/sshd_config IgnoreUserKnownHosts yes If the value is returned as "no", the returned line is commented out, or no output is returned, this is a finding.
✔️ Fix
Configure the SSH daemon to not allow authentication using known host's authentication. Add the following line in "/etc/ssh/sshd_config" or uncomment the line and set the value to "yes": IgnoreUserKnownHosts yes The SSH daemon must be restarted for the changes to take effect. To restart the SSH daemon, run the following command: $ sudo systemctl restart sshd.service