Title

Windows Server 2019 must be configured to ignore NetBIOS name release requests except from WINS servers. (Cat III impact)

Discussion

Configuring the system to ignore name release requests, except from WINS servers, prevents a denial of service (DoS) attack. The DoS consists of sending a NetBIOS name release request to the server for each entry in the server's cache, causing a response delay in the normal operation of the server's WINS resolution capability.

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: \SYSTEM\CurrentControlSet\Services\Netbt\Parameters\ Value Name: NoNameReleaseOnDemand Value Type: REG_DWORD Value: 0x00000001 (1)

Fix Text

Configure the policy value for Computer Configuration >> Administrative Templates >> MSS (Legacy) >> "MSS: (NoNameReleaseOnDemand) Allow the computer to ignore NetBIOS name release requests except from WINS servers" to "Enabled". This policy setting requires the installation of the MSS-Legacy custom templates included with the STIG package. "MSS-Legacy.admx" and "MSS-Legacy.adml" must be copied to the \Windows\PolicyDefinitions and \Windows\PolicyDefinitions\en-US directories respectively.

Additional Identifiers

Rule ID: SV-205819r958902_rule

Vulnerability ID: V-205819

Group Title: SRG-OS-000420-GPOS-00186

Expert Comments

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