Microsoft Security Advisory 2607712 – Fraudulent Digital Certificates Could Allow Spoofing: http://www.microsoft.com/technet/security/advisory/2607712.mspx
Microsoft is aware of active attacks using at least one fraudulent digital certificate issued by DigiNotar, a certification authority present in the Trusted Root Certification Authorities Store. A fraudulent certificate could be used to spoof content, perform phishing attacks, or perform man-in-the-middle attacks against all Web browser users including users of Internet Explorer. While this is not a vulnerability in a Microsoft product, this issue affects all supported releases of Microsoft Windows.
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