One of the largest Botnet "Sirefef" disrupted by Microsoft

Microsoft teamed up with law enforcement agencies and A10 Networks has disrupted one of the world's largest Botnet "ZeroAccess" that defrauded online advertisers.

ZeroAccess also known as Sirefef is a notorious malware which makes money for cyber criminals through Click fraud - Hijacking victim's search results and generating fake clicks on ads. It also installs Bitcoin miners in the infected machines.

Victims usually get infected by the ZeroAccess through drive by download attacks.

The malware has reportedly infected more than two million computers. It costs online advertisers around $2.7 million per month.

David Finn, executive director and associate general counsel of the Microsoft Digital Crimes Unit said the disruption "will stop victims’ computers from being used for fraud and help us identify the computers that need to be cleaned of the infection"

Microsoft said the action will not "fully eliminate the ZeroAccess botnet due to the complexity of the threat". However, it will significantly disrupt the botnet's operation and will bring loss of revenue for the cyber criminals who behind the ZeroAccess.