If you’re even remotely interested in Windows security, you’ve probably seen the sensationalist claims from Steve Gibson that the WMF vulnerability was actually a secret backdoor into Windows, deliberately placed there by Microsoft.
I’ve tried to steer clear of this claim so far, because the last thing I want to do is add to the hype over what is at best a highly suspect conspiracy theory. I thought the explanation and rebuttal from Stephen Toulouse of the Microsoft Security Response Center made good sense, but I also understand that some people are going to be justifiably skeptical of any official statement that comes out of Redmond.
But I’ve just run across Mark Russinovich’s detailed analysis of Gibson’s claim, and I feel confident that his conclusion is correct:
In my opinion the backdoor is one caused by a security flaw and not one made for subterfuge.
Mark’s body of work and impressive library of utilities at Sysinternals proves that he knows more about the guts of Windows than just about anyone else on the planet, including lots of Microsoft lifers. He’s also the guy who broke the Sony rootkit story.
When Mark says there’s no conspiracy, that ends the discussion for me.
Ed Bott 
Since when is Steve Gibson’s opinion chopped liver?? They both have a long list of credentials and history. Sounds like a classic case of he said / she said.
Personally i like the conspiracy theory. Tech companies are becoming increasingly distrustful and it makes for a better story to gossip about.
This particular bug may not have been a backdoor, but that does not remove the possiblity of backdoors in Windows. Microsoft is a large organisation that compartments and strictly regulates access to source code. It would only take one, or a few, people to insert such a change, for any one of the classic reasons – MICE = Money, Ideology, Conscience, Ego. Intelligence agencies know that they are the targets of infiltration and they still get burned.