Windows Server 2019 session security for NTLM SSP-based clients must be configured to require NTLMv2 session security and 128-bit encryption.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-205921 | WN19-SO-000330 | SV-205921r991589_rule | Medium |
| 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. |
| STIG | Date |
| Microsoft Windows Server 2019 Security Technical Implementation Guide | 2025-01-15 |
Details
| Check Text (C-6186r356125_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: NTLMMinClientSec Value Type: REG_DWORD Value: 0x20080000 (537395200) |
| Fix Text (F-6186r356126_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) clients" to "Require NTLMv2 session security" and "Require 128-bit encryption" (all options selected). |