Insecure logons to an SMB server must be disabled.

From Windows Server 2016 Security Technical Implementation Guide

Associated with: CCI-000366

SV-88159r1_rule Insecure logons to an SMB server must be disabled.

Vulnerability discussion

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

Check content

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 text

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

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