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 | 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 | 2024-12-04 |
Details
| Check Text (C-61746r952205_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 |