Title

Insecure logons to an SMB server must be disabled. (Cat II impact)

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".

Additional Identifiers

Rule ID: SV-224920r991589_rule

Vulnerability ID: V-224920

Group Title: SRG-OS-000480-GPOS-00227

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.