Insecure logons to an SMB server must be disabled.

Severity
Group ID
Group Title
Version
Rule ID
Date
STIG Version
mediumV-220802SRG-OS-000480-GPOS-00227WN10-CC-000040SV-220802r991589_rule2025-02-253
Description
Insecure guest logons allow unauthenticated access to shared folders. Shared resources on a system must require authentication to establish proper access.
ℹ️ Check
Windows 10 v1507 LTSB version does not include this setting; it is NA for those systems. 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
Configure the policy value for Computer Configuration >> Administrative Templates >> Network >> Lanman Workstation >> "Enable insecure guest logons" to "Disabled".