Ok, earlier this morning we activated our Software Security Incident Reponse Process to respond to a malicious attack known as Worm:Win32/Zotob.A. Our investigation has determined that only a small number of customers have been affected and we're working directly with them. We have seen no indication of widespread impact to the Internet, but we have posted a guidance page as well as an encyclopedia entry on this attack.
via the MSRC Blog.
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