OL 9 SSH daemon must perform strict mode checking of home directory configuration files.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-271714 | OL09-00-002351 | SV-271714r1091854_rule | Medium |
| Description |
| If other users have access to modify user-specific SSH configuration files, they may be able to log into the system as another user. |
| STIG | Date |
| Oracle Linux 9 Security Technical Implementation Guide | 2025-05-08 |
Details
| Check Text (C-75764r1091852_chk) |
| Verify that OL 9 SSH daemon performs strict mode checking of home directory configuration files 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*strictmodes' StrictModes yes If the "StrictModes" keyword is set to "no", the returned line is commented out, or no output is returned, this is a finding. |
| Fix Text (F-75671r1091853_fix) |
| Configure the SSH daemon to perform strict mode checking of home directory configuration files. 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": StrictModes yes The SSH service must be restarted for changes to take effect: $ sudo systemctl restart sshd.service |