The SSH daemon must be configured to only use Message Authentication Codes (MACs) employing FIPS 140-2 approved cryptographic hash algorithms.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-22460	GEN005507	SV-37826r3_rule		Medium

Description
DoD information systems are required to use FIPS 140-2 approved cryptographic hash functions.

STIG	Date
Red Hat Enterprise Linux 5 Security Technical Implementation Guide	2017-03-01

Details

Check Text ( C-37026r2_chk )
Check the SSH daemon configuration for allowed MACs. Procedure: # grep -i macs /etc/ssh/sshd_config | grep -v '^#' If no lines are returned, or the returned MACs list contains any MAC that is not hmac-sha1 or a better hmac algorithm that is on the FIPS 140-2 approved list, this is a finding.

Fix Text (F-32294r3_fix)
Edit the SSH daemon configuration and remove any MACs that are not hmac-sha1 or a better hmac algorithm that is on the FIPS 140-2 approved list. If necessary, add a MACs line. Restart the SSH daemon. # /sbin/service sshd restart