Windows 11 • Release: 6 Benchmark Date: 05 Jan 2026

CAT II V-253360 WN11-CC-000040

Insecure logons to an SMB server must be disabled.

Documentable No
Rule ID SV-253360r991589_rule
CCI References
CCI-000366

Insecure guest logons allow unauthenticated access to shared folders. Shared resources on a system must require authentication to establish proper access.

Check Procedure

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: \SOFTWARE\Policies\Microsoft\Windows\LanmanWorkstation\

Value Name: AllowInsecureGuestAuth

Type: REG_DWORD
Value: 0x00000000 (0)

Fix Action

Configure the policy value for Computer Configuration >> Administrative Templates >> Network >> Lanman Workstation >> "Enable insecure guest logons" to "Disabled".