Windows Server 2019 must prevent NTLM from falling back to a Null session.
An XCCDF Rule
Description
NTLM sessions that are allowed to fall back to Null (unauthenticated) sessions may gain unauthorized access.
- ID
- SV-205917r991589_rule
- Version
- WN19-SO-000270
- Severity
- Medium
- References
- Updated
Remediation Templates
A Manual Procedure
Configure the policy value for Computer Configuration >> Windows Settings >> Security Settings >> Local Policies >> Security Options >> "Network security: Allow LocalSystem NULL session fallback" to "Disabled".