STIGQter: STIG Summary: Oracle Linux 9 Security Technical Implementation Guide Version: 1 Release: 6 Benchmark Date: 01 Jul 2026:

OL 9 SSH client must be configured to use only DOD-approved encryption ciphers employing FIPS 140-3 validated cryptographic hash algorithms to protect the confidentiality of SSH client connections.

DISA Rule

SV-271489r1184190_rule

Vulnerability Number

V-271489

Group Title

SRG-OS-000250-GPOS-00093

Rule Version

OL09-00-000261

Severity

CAT I

CCI(s)

CCI-001453 - Implement cryptographic mechanisms to protect the integrity of remote access sessions.

Weight

Fix Recommendation

Configure the SSH client to use only ciphers employing FIPS 140-3 approved algorithms.

Reinstall crypto-policies with the following command:

$ sudo dnf -y reinstall crypto-policies

Set the crypto-policy to FIPS with the following command:

$ sudo update-crypto-policies --set FIPS

Setting system policy to FIPS

Note: Systemwide crypto policies are applied on application startup. It is recommended to restart the system for the change of policies to fully take place.

Check Contents

Verify OL 9 is configured so that the SSH client uses only ciphers employing FIPS 140-3 approved algorithms.

To verify the ciphers in the systemwide SSH configuration file, use the following command:

$ grep -i Ciphers /etc/crypto-policies/back-ends/openssh.config
Ciphers aes256-gcm@openssh.com,aes256-ctr,aes128-gcm@openssh.com,aes128-ctr

If the cipher entries in the "openssh.config" file have any ciphers other than "aes256-gcm@openssh.com,aes256-ctr,aes128-gcm@openssh.com,aes128-ctr", or they are missing or commented out, this is a finding.

Vulnerability Number

V-271489

Documentable

False

Rule Version

OL09-00-000261

Severity Override Guidance

Check Content Reference

Target Key

5680