We've seen a report that the author of the Bozori (or Zotob) worm has been arrested in Morocco.

It's unusual for an arrest to take place so soon after the release of malicious code. Perhaps it's not only the time-lag between vulnerability and exploit that is being reduced.

The anatomy of the Bozori worm outbreaks that we've seen in the last day or so leads us to believe that we're witnessing the emergence of a new type of infection, what we're calling the 'business worm'.

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We've decided to rename Net-Worm.Win32.Small.d to Net-Worm.Win32.Bozori.a.

Infection reports are coming mostly from the USA, with some high-profile targets being hit.

Shortly after Bozori.a was detected we found Bozori.b. This variant doesn't seem very widespread at the moment.

Instead of wintbp.exe, Bozori.b has wintbpx.exe as the filename. Otherwise the two variants don't differ much, both around 10KB in size.

Bozori.b's MD5: 7ef9b103143c15563ee386846fd4db77

The worm makes use of an exploit to get introduced to the system. And this exploit is a buffer overflow which is likely to result in a crash of services.exe.
This will lead to the infamous "System Shutdown" pop-up box made notorious by Lovsan and Sasser.

With only 60 seconds on the clock, administrators will have a tough time cleaning this mess up.