Windows 11 • Release: 6 Benchmark Date: 05 Jan 2026

CAT II V-253353 WN11-CC-000020

IPv6 source routing must be configured to highest protection.

Documentable No
Rule ID SV-253353r991589_rule
CCI References
CCI-000366

Configuring the system to disable IPv6 source routing protects against spoofing.

Check Procedure

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\Tcpip6\Parameters\

Value Name: DisableIpSourceRouting

Value Type: REG_DWORD
Value: 2

Fix Action

Configure the policy value for Computer Configuration >> Administrative Templates >> MSS (Legacy) >> "MSS: (DisableIPSourceRouting IPv6) IP source routing protection level (protects against packet spoofing)" to "Highest protection, source routing is completely disabled".

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.