The new worm, DoomJuice.B, sets random HTTP headers to make it more difficult to filter the attack traffic, seeking to work around a defensive measure used by Microsoft earlier this week, when dropped requests without User-Agent headers to differentiate between Web browsers and the DDoS attack agents. The DoomJuice.B DDoS also initiates twice as many requests as its predecessor, launching 32-192 parallel threads instead of the 16-96 of DoomJuice.A.
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