[ConservativeMind]

It does not necessarily follow that any program is using the vulnerability.

This issue could be with what the antivirus programs prevent in the form of changes by Windows, of which the latest patches may address microcode updates Microsoft would never put on a system (usually separate BIOS or Intel update), because they may have to go on before Microsoft can safely reference them.

[ImJustAnotherOkie]

Microsoft's testing revealed a "small number" of antivirus programs are making unsupported calls into Windows kernel memory, which result in blue screen of death (BSOD) errors.

Like you all I know is what I read in the papers.

http://www.zdnet.com/article/windows-meltdown-spectre-patches-if-you-havent-got-them-blame-your-antivirus/