OL 9 must not allow users to override SSH environment variables.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-271720 | OL09-00-002358 | SV-271720r1091872_rule | CCI-000366 | medium |
| Description | ||||
| SSH environment options potentially allow users to bypass access restriction in some configurations. | ||||
| STIG | Date | |||
| Oracle Linux 9 Security Technical Implementation Guide | 2025-05-08 | |||
Related Frameworks
4 paths across 3 frameworks
Related Frameworks
NIST 800-531 mapping
CM-6
1.00
- DISA · 1 · disa_xccdf · related
- DISA · 2025-01-23 · disa_cci_list · equivalent
NIST 800-1712 mappings
3.4.1
1.00
- DISA · 1 · 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 · 1 · 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 · 1 · disa_xccdf · related
Details
Check Text (C-271720r1091872_chk)
Verify that OL 9 does not allow users to override SSH environment variables.
Verify that unattended or automatic logon 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 -iH '^\s*permituserenvironment'
PermitUserEnvironment no
If "PermitUserEnvironment" is set to "yes", is missing completely, or is commented out, this is a finding.
Fix Text (F-75677r1091871_fix)
Configure the OL 9 SSH daemon to not allow unattended or automatic logon to the system.
Add or edit the following line in the "/etc/ssh/sshd_config" or in a file in "/etc/ssh/sshd_config.d":
PermitUserEnvironment no
Restart the SSH daemon for the setting to take effect:
$ sudo systemctl restart sshd.service