More than 2 million computers worldwide were infected with malicious software in a “massive fraud scheme” that the U.S. disabled as part of a criminal investigation, the Justice Department said.

The department filed a civil complaint, criminal seizure warrants and issued a temporary restraining order in coordinated action with Microsoft Corp., which issued a software patch yesterday to correct a vulnerability in its Windows operating system. The vulnerability allowed the software to spread from one computer to another creating a so-called botnet.

The action was aimed at software called Coreflood, which collects passwords and financial information that was used by criminals, the Justice Department said in a statement today. The group of computers infected with Coreflood, known as the Coreflood botnet, is suspected by the U.S. of operating for almost a decade and infecting more than 1.8 million computers in the U.S. alone.

via Computer Network Used in ‘Massive’ Fraud Targeted by U.S. – Businessweek.