The US Justice Department has shut down a massive botnet network, Coreflood, by taking over the servers used to control the network and sending a stop command to the compromised PCs that disables installed malware.

A court order allowed the Internet Systems Consortium (ISC) to swop the servers being used to control the botment with others tasked with cleaning up the infected machines around the world.
A botnet is a network of computers used – without their owners’ knowledge or consent – to send spam and malware. They are under the control of centralized servers.
The Justice Department has swopped out the Coreflood servers and, from Tuesday evening, began collecting the IP addresses of affected PCs. It has already sent a shutdown command to all US-based PCs infected.
Coreflood is thought to have infected more than 2-million PCs around the world, and may have led to the theft of more than $100-million using key-logging software to steal user names, passwords and other information.
The move against Coreflood follows March’s raid by law enforcement agencies and Microsoft to shut down the Rustock botnet.