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

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-252942	TOSS-04-010400	SV-252942r824150_rule		Medium

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.

STIG	Date
Tri-Lab Operating System Stack (TOSS) 4 Security Technical Implementation Guide	2022-08-29

Details

Check Text ( C-56395r824148_chk )
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 Text (F-56345r824149_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