The SSH client 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-22463	GEN005512	SV-26756r2_rule		Medium

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

STIG	Date
AIX 6.1 SECURITY TECHNICAL IMPLEMENTATION GUIDE	2018-09-18

Details

Check Text ( C-27765r2_chk )
Check the SSH client configuration for allowed MACs. Procedure: # grep -i macs /etc/ssh/ssh_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-24006r2_fix)
Edit the SSH client 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.