Hmm obviously I read the article too quickly, this attack does not depend on loading a kernel driver. My bad ;)

Yep. Furthermore this requires not just admin privileges, but also being able to load a kernel module which has been severely restricted under 64-bit Windows (the driver's catalog has to be signed by Microsoft). Still, many people use Windows XP with an admin account, but the flaw itself does not lie with the AV themselves -- a few of them will even warn when a program attemps to load a unsigned kernel driver. KAV also warns when running an unsigned program from outside Program Files.

However for compatibility with existing malware^W legitimate corporate drivers, Microsoft decided not to block the loading of unsigned kernel drivers in Windows 7 32-bit. In fact NX protection is neither enabled by default in 32 and 64-bit versions (it can be enabled manually in the "Advanced systems settings" tab).