The service principal name (SPN) target name validation level must be turned off.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
|---|---|---|---|---|
| V-21950 | WN12-SO-000035 | SV-53175r1_rule | Medium |
| Description |
|---|
| If a service principle name (SPN) is provided by the client, it is validated against the server's list of SPNs. Implementation may disrupt file and print sharing capabilities. |
| STIG | Date |
|---|---|
| Windows Server 2012/2012 R2 Domain Controller Security Technical Implementation Guide | 2020-06-16 |
Details
| Check Text ( C-47481r1_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\Services\LanmanServer\Parameters\ Value Name: SmbServerNameHardeningLevel Type: REG_DWORD Value: 0 |
| Fix Text (F-46101r1_fix) |
|---|
| Configure the policy value for Computer Configuration -> Windows Settings -> Security Settings -> Local Policies -> Security Options -> "Microsoft network server: Server SPN target name validation level" to "Off". |