ZDNet India : 'Witty' worm infects, dies quickly
Using a manner of infection similar to the fast-spreading Slammer worm, the Witty program compromised more than 20,000 machines in less than an hour."Because it crashes the machines eventually, (the worm) died off really fast," Ullrich said. He estimated that almost 30,000 computer had been infected by the worm, and most of them had crashed because of file corruption within 30 minutes of being infected.

An unknown author created the worm about two days after news of the flaw became public, in what may be the fastest turnaround of malicious code writing to date. "It is the only time that I can think of that this had happened so quickly," Ingevaldson said. "This was surprising. We didn't think we would see something that could come up this big and fast."