The Ubuntu operating system must not allow unattended or automatic login via SSH.
Severity | Group ID | Group Title | Version | Rule ID | Date | STIG Version |
|---|---|---|---|---|---|---|
| high | V-238218 | SRG-OS-000480-GPOS-00229 | UBTU-20-010047 | SV-238218r991591_rule | 2025-03-03 | 2 |
| Description |
|---|
| Failure to restrict system access to authenticated users negatively impacts Ubuntu operating system security. |
| ℹ️ Check |
|---|
| Verify that unattended or automatic login via SSH is disabled with the following command: $ sudo /usr/sbin/sshd -dd 2>&1 | awk '/filename/ {print $4}' | tr -d '\r' | tr '\n' ' ' | xargs sudo grep -iEH '^\s*(permit(.*?)(passwords|environment))' PermitEmptyPasswords no PermitUserEnvironment no If "PermitEmptyPasswords" or "PermitUserEnvironment" keywords are not set to "no", are missing completely, or are commented out, this is a finding. If conflicting results are returned, this is a finding. |
| ✔️ Fix |
|---|
| Configure the Ubuntu operating system to allow the SSH daemon to not allow unattended or automatic login to the system. Add or edit the following lines in the "/etc/ssh/sshd_config" file: PermitEmptyPasswords no PermitUserEnvironment no Restart the SSH daemon for the changes to take effect: $ sudo systemctl restart sshd.service |