The SSH daemon must be configured to only use the SSHv2 protocol.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-39412	SRG-OS-000112-ESXI5	SV-51270r1_rule		High

Description
SSHv1 is not a DoD-approved protocol and has many well-known vulnerability exploits. Exploits of the SSH daemon could provide immediate root access to the system.

STIG	Date
VMware ESXi Server 5.0 Security Technical Implementation Guide	2017-01-06

Details

Check Text ( C-46686r1_chk )
Disable lock down mode. Enable the ESXi Shell. Check the SSH daemon configuration for required protocol. # grep -i "Protocol 2" /etc/ssh/sshd_config | grep -v '^#' Re-enable lock down mode. If no lines are returned, or the returned protocol list contains anything except 2, this is a finding.

Fix Text (F-44425r1_fix)
Disable lock down mode. Enable the ESXi Shell. Edit the SSH daemon configuration and add/modify the "Protocol" configuration for Protocol 2 only. # vi /etc/ssh/sshd_config Re-enable lock down mode.