RHEL 9 SSH daemon must not allow rhosts authentication.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-258005	RHEL-09-255145	SV-258005r1045069_rule	CCI-000366	medium
Description
SSH trust relationships mean a compromise on one host can allow an attacker to move trivially to other hosts.
STIG			Date
Red Hat Enterprise Linux 9 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-258005r1045069_chk)

Verify the SSH daemon does not allow rhosts 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*ignorerhosts' IgnoreRhosts 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-61670r1045068_fix)

Configure the SSH daemon to not allow rhosts authentication. Add the following line to "/etc/ssh/sshd_config" or to a file in "/etc/ssh/sshd_config.d", or uncomment the line and set the value to "yes": IgnoreRhosts yes The SSH service must be restarted for changes to take effect: $ sudo systemctl restart sshd.service