Title

The system is configured to allow name-release attacks. (Cat III impact)

Discussion

Prevents a denial-of-service (DoS) attack against a WINS server. The DoS consists of sending a NetBIOS Name Release Request to the server for each entry in the servers cache, causing a response delay in the normal operation of the servers WINS resolution capability.

Check Content

Analyze the system using the Security Configuration and Analysis snap-in. Expand the Security Configuration and Analysis tree view. Navigate to Local Policies -> Security Options. If the value for “MSS: (NoNameReleaseOnDemand) Allow computer to ignore NetBIOS name release requests except from WINS servers” is not set to “Enabled”, then this is a finding. The policy referenced configures the following registry value: Registry Hive: HKEY_LOCAL_MACHINE Registry Path: \System\CurrentControlSet\Services\Netbt\Parameters\ Value Name: NoNameReleaseOnDemand Value Type: REG_DWORD Value: 1 Note: The NetBIOS name for the system will no longer appear under ‘My Network Places’.

Fix Text

Configure the policy value for Computer Configuration -> Windows Settings -> Security Settings -> Local Policies -> Security Options -> “MSS: (NoNameReleaseOnDemand) Allow computer to ignore NetBIOS name release requests except from WINS servers” to “Enabled”.

Additional Identifiers

Rule ID: SV-4116r1_rule

Vulnerability ID: V-4116

Group Title: Name-Release Attacks

Expert Comments

CCIs tied to check.

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