Microsoft Windows Server 2019

Windows Server 2019 session security for NTLM SSP-based servers must be configured to require NTLMv2 session security and 128-bit encryption

STIG ID: WN19-SO-000340 | SRG: SRG-OS-000480-GPOS-00227 | Severity: Medium | CCI: CCI-000366 | Vulnerability ID: V-205922

Description

Microsoft has implemented a variety of security support providers for use with Remote Procedure Call (RPC) sessions. All of the options must be enabled to ensure the maximum security level.

Check

C-6187r356128_chk

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\Control\Lsa\MSV1_0\Value Name: NTLMMinServerSecValue Type: REG_DWORDValue: 0x20080000 (537395200)

Fix

F-6187r356129_fix

Configure the policy value for Computer Configuration >> Windows Settings >> Security Settings >> Local Policies >> Security Options >> "Network security: Minimum session security for NTLM SSP based (including secure RPC) servers" to "Require NTLMv2 session security" and "Require 128-bit encryption" (all options selected).