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-39403	SRG-OS-000158-ESXI5	SV-51261r1_rule		Medium

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

STIG	Date
VMware ESXi Server 5.0 Security Technical Implementation Guide	2013-09-12

Details

Check Text ( C-46677r1_chk )
Disable lock down mode. Enable the ESXi Shell. Check the SSH client configuration for allowed MACs. # grep -i macs /etc/ssh/ssh_config | grep -v '^#' Re-enable lock down mode. If no lines are returned, or the returned MACs list contains any MAC other than hmac-sha1, this is a finding.

Fix Text (F-44416r1_fix)
Disable lock down mode. Enable the ESXi Shell. Edit the SSH client configuration and add/modify the "MAC" configuration (example of allowed cipher: hmac-sha1). # vi /etc/ssh/ssh_config Re-enable lock down mode.