The TOSS SSH daemon must perform strict mode checking of home directory configuration files.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-253106 | TOSS-04-040650 | SV-253106r991589_rule | Medium |
| Description |
| If other users have access to modify user-specific SSH configuration files, they may be able to log on to the system as another user. |
| STIG | Date |
| Tri-Lab Operating System Stack (TOSS) 4 Security Technical Implementation Guide | 2025-05-08 |
Details
| Check Text (C-56559r824988_chk) |
| Verify the SSH daemon performs strict mode checking of home directory configuration files with the following command: $ sudo grep -i strictmodes /etc/ssh/sshd_config StrictModes yes If "StrictModes" is set to "no", is missing, or the returned line is commented out, this is a finding. |
| Fix Text (F-56509r824989_fix) |
| Configure SSH to perform strict mode checking of home directory configuration files. Uncomment the "StrictModes" keyword in "/etc/ssh/sshd_config" and set the value to "yes": StrictModes 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 |