"Indestructable" Botnet Discovered

Jul 1, 2011, 15:45 by Sarah Long

Russian security researchers say a botnet of more than 4.5 million virus-infected computers spreading e-mail spam and malware is "practically indestructible."

Researchers at Kaspersky Labs said the botnet, called TDL-4, is being expanded via rogue Web sites offering pornography and pirated content, The Daily Telegraph said.

Operators of the sites receive $20 to $200 from the criminals behind the botnet for every 1,000 new machines they infect, Kaspersky Labs said.

A botnet is a network of virus-infected computers, sometimes known as "zombies," remotely controlled by cyber criminals.

TDL-4 infected 4.5 million machines in just the first three months of this year, Kaspersky researchers said, with about a third of the computers in the United States.

The computer virus used in TDL-4 use a very sophisticated array of techniques to hide from anti-virus software and strongly resists attempts to remove it from infected machines, the researchers said.

"The owners of TDL are essentially trying to create an 'indestructible' botnet that is protected against attacks, competitors and anti-virus companies," Kaspersky's Sergey Golovanov and Igor Soumenkov said.

"The [TDL-4] botnet, with more than 4.5 million infected computers, is used by cyber criminals to manipulate adware and search engines, provide anonymous Internet access and acts as a launch pad for other malware," they said.

Source: UPI