Vulnerability Discussion
A computer connecting to a domain controller will establish a secure channel. Requiring strong session keys enforces 128-bit encryption between systems.
Check
If the following registry value does not exist or is not configured as specified, this is a finding:
Registry Hive: HKEY_LOCAL_MACHINE
Registry Path: \SYSTEM\CurrentControlSet\Services\Netlogon\Parameters\
Value Name: RequireStrongKey
Value Type: REG_DWORD
Value: 1
Warning: This setting may prevent a system from being joined to a domain if not configured consistently between systems.
Fix
Configure the policy value for Computer Configuration >> Windows Settings >> Security Settings >> Local Policies >> Security Options >> "Domain member: Require strong (Windows 2000 or Later) session key" to "Enabled".