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
GEN005507-ESXI5-000099	GEN005507-ESXI5-000099	GEN005507-ESXI5-000099_rule		Medium

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

STIG	Date
VMware ESXi v5 Security Technical Implementation Guide	2013-01-15

Details

Check Text ( C-GEN005507-ESXI5-000099_chk )
Disable lock down mode. Enable the ESXi Shell. Check the SSH daemon configuration for allowed MACs. # grep -i macs /etc/ssh/sshd_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-GEN005507-ESXI5-000099_fix)
Disable lock down mode. Enable the ESXi Shell. Edit the SSH daemon configuration and add/modify the "MAC" configuration (example of allowed cipher: hmac-sha1). # vi /etc/ssh/sshd_config Re-enable lock down mode.