Windows Server 2019 must not allow anonymous enumeration of shares.

Overview

Finding IDVersionRule IDIA ControlsSeverity
V-205724WN19-SO-000230SV-205724r958524_ruleCCI-001090high
Description
Allowing anonymous logon users (null session connections) to list all account names and enumerate all shared resources can provide a map of potential points to attack the system.
STIGDate
Microsoft Windows Server 2019 Security Technical Implementation Guide2025-05-23

Details

Check Text (C-205724r958524_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\ Value Name: RestrictAnonymous Value Type: REG_DWORD Value: 0x00000001 (1)

Fix Text (F-5989r355091_fix)

Configure the policy value for Computer Configuration >> Windows Settings >> Security Settings >> Local Policies >> Security Options >> "Network access: Do not allow anonymous enumeration of SAM accounts and shares" to "Enabled".