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V-252942

CAT II (Medium)

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

Rule ID

SV-252942r991589_rule

STIG

Tri-Lab Operating System Stack (TOSS) 4 Security Technical Implementation Guide

Version

V2R5

CCIs

CCI-000366

Discussion

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.

Check Content

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

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