Check: 3.076
Windows Vista STIG:
3.076
(in versions v6 r42 through v6 r41)
Title
The system is not configured to meet the minimum requirement for session security for NTLM SSP based Clients. (Cat II impact)
Discussion
Microsoft has implemented a variety of security support providers for use with RPC sessions. In a homogenous Windows environment, all of the options should be enabled and testing should be performed in a heterogeneous environment to determine the maximum-security level that provides reliable functionality.
Check Content
Analyze the system using the Security Configuration and Analysis snap-in. Expand the Security Configuration and Analysis tree view. Navigate to Local Policies -> Security Options. If the value for “Network security: Minimum session security for NTLM SSP based (including secure RPC) clients” is not set to “Require NTLMv2 session security” and “Require 128-bit encryption”, then this is a finding. The policy referenced configures the following registry value: Registry Hive: HKEY_LOCAL_MACHINE Registry Path: \System\CurrentControlSet\Control\Lsa\MSV1_0\ Value Name: NTLMMinClientSec Value Type: REG_DWORD Value: 0x20080000 (537395200) Warnings: Microsoft warns that setting these may prevent the client from communicating with legacy servers that do not support them. “Require NTLMv2 session security” will prevent authentication, if the “Network security: LAN Manager Authentication level” is set to permit NTLM or LM authentication. Documentable Explanation: If these settings need to be modified in a mixed Windows environment, the changes should be documented with the IAO.
Fix Text
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”, ”Require 128-bit encryption” (all options selected).
Additional Identifiers
Rule ID: SV-15980r1_rule
Vulnerability ID: V-3382
Group Title: Session Security for NTLM SSP Based Clients
Expert Comments
CCIs
Number | Definition |
---|---|
CCI-000366 |
The organization implements the security configuration settings. |
Controls
Number | Title |
---|---|
CM-6 |
Configuration Settings |