Microsoft’s Digital Crimes Unit has effectively shut down the Waledac botnet, cutting off cybercriminal access to hundreds of thousands of infected Windows computers around the world.

In partnership with security vendors and law enforcement officials, Microsoft implemented “Operation b49″ and moved to the federal courts to get a temporary restraining order cutting off 277 Internet domains believed to be run by criminals as the Waledac bot.

According to Microsoft associate general counsel Tim Cranton, the action quickly and effectively cut off traffic to Waledac at the “.com” or domain registry level, severing the connection between the command and control centers of the botnet and most of its thousands of zombie computers around the world.

Waledac is one of the 10 largest botnets in the US and is responsible to distributing billions of spam messages around the world. According to Microsoft, the botnet is estimated to have infected hundreds of thousands of computers around the world and, prior to this action, was believed to have the capacity to send over 1.5 billion spam emails per day.

Read the entire article at Microsoft's *Operation b49* chokes Waledac botnet