Online criminals have <A HREF="http://blogs.zdnet.com/security/?p=169&tag=nl.e589">pounced on the unpatched Windows DNS Server service vulnerability,</A> using the security hole to seed and replenish for-profit botnets. The latest twist in the ongoing attacks comes less than a week after Microsoft's pre-patch advisory provided clues for hackers to write and release detailed exploit code.

Anti-virus researchers have detected signs of a variant of the talkative Nirbot Trojan squirming through the worm hole created by the vulnerability. According to data from Arbor's ATLAS threat monitoring portal, the bulk of the attacks are coming from the U.S., China, India and Korea.