UCF STIG Viewer Logo
Changes are coming to https://stigviewer.com. Take our survey to help us understand your usage and how we can better serve you in the future.
Take Survey

The SSH daemon must be configured to use only FIPS 140-2 approved ciphers.


Overview

Finding ID Version Rule ID IA Controls Severity
V-38617 RHEL-06-000243 SV-50418r1_rule Medium
Description
Approved algorithms should impart some level of confidence in their implementation. These are also required for compliance.
STIG Date
Red Hat Enterprise Linux 6 Security Technical Implementation Guide 2016-06-05

Details

Check Text ( C-46176r1_chk )
Only FIPS-approved ciphers should be used. To verify that only FIPS-approved ciphers are in use, run the following command:

# grep Ciphers /etc/ssh/sshd_config

The output should contain only those ciphers which are FIPS-approved, namely, the AES and 3DES ciphers.
If that is not the case, this is a finding.
Fix Text (F-43566r1_fix)
Limit the ciphers to those algorithms which are FIPS-approved. Counter (CTR) mode is also preferred over cipher-block chaining (CBC) mode. The following line in "/etc/ssh/sshd_config" demonstrates use of FIPS-approved ciphers:

Ciphers aes128-ctr,aes192-ctr,aes256-ctr,aes128-cbc,3des-cbc,aes192-cbc,aes256-cbc

The man page "sshd_config(5)" contains a list of supported ciphers.