Windows Server 2025 must not allow anonymous enumeration of shares.
Severity | Group ID | Group Title | Version | Rule ID | Date | STIG Version |
|---|---|---|---|---|---|---|
| high | V-278217 | SRG-OS-000138-GPOS-00069 | WN25-SO-000230 | SV-278217r1181357_rule | 2026-02-20 | 1 |
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.
ℹ️ Check
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
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".