A Google security researcher releases code to expose a flaw that affects every release of the Windows NT kernel. Microsoft has released a security advisory to acknowledge the issue and warn of the risk of privilege escalation attacks. The flaw does not affect Windows operating systems for x64-based and Itanium-based computers, Microsoft said. Microsoft was notified about the issue in June 2009, researcher Tavis Ormandy who released the flaw details says Microsoft was not aware of the issue for several months and decided it was in the best interest of everyone to go public.
Source: https://threatpost.com/microsoft-confirms-unpatched-windows-kernel-flaw-012110/73408/