The RHEL 8 SSH daemon must not allow authentication using known host’s authentication.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-230290	RHEL-08-010520	SV-230290r1069302_rule	CCI-000366	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
Red Hat Enterprise Linux 8 Security Technical Implementation Guide			2025-05-14

Related Frameworks

4 paths across 3 frameworks

NIST 800-531 mapping

CM-6

1.00

DISA · 2 · disa_xccdf · related
DISA · 2025-01-23 · disa_cci_list · equivalent

NIST 800-1712 mappings

3.4.1

1.00

DISA · 2 · disa_xccdf · related
DISA · 2025-01-23 · disa_cci_list · equivalent
NIST · Rev 2 (Feb 2020, errata Jan 2021) · nist_800_171_app_d · equivalent

3.4.2

1.00

DISA · 2 · disa_xccdf · related
DISA · 2025-01-23 · disa_cci_list · equivalent
NIST · Rev 2 (Feb 2020, errata Jan 2021) · nist_800_171_app_d · equivalent

CCI1 mapping

CCI-000366

1.00

DISA · 2 · disa_xccdf · related

Details

Check Text (C-230290r1069302_chk)

Verify the SSH daemon does not allow authentication using known host’s 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 the value is returned as "no", the returned line is commented out, or no output is returned, this is a finding. If conflicting results are returned, this is a finding.

Fix Text (F-32934r567617_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