Microsoft released an advisory [1] earlier today announcing that they will place a number of DigiNotar root certificates on the "not trusted" list. 

A blog article further explains how certificate stores can be manipulated manually [2].

One important difference between this most recent advisory, and an earlier advisory [3] is that Windows Mobile 6.x/7/7.5 is no longer listed as affected. The earlier advisory stated that Windows Mobile 6.x and 7 are affected. It didn't mention Windows Mobile 7.5. (thanks to a read for pointing this out)

[1]http://www.microsoft.com/technet/security/advisory/2607712.mspx
[2]http://blogs.technet.com/b/srd/archive/2011/09/04/protecting-yourself-from-attacks-that-leverage-fraudulent-diginotar-digital-certificates.aspx
[3] http://technet.microsoft.com/en-us/security/advisory/2524375

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Johannes B. Ullrich, Ph.D.
SANS Technology Institute
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