Most people only know Microsoft for its software, with Windows and Office being the most well known. But did you know the company is also pretty involved in combating cyber crime? Earlier this year, for example, Microsoft partnered with the FBI to tackle the Citadel botnet after it was used to steal upwards of half a billion dollars over the prior 18 months. Meanwhile, Microsoft’s Malware Protection Center does its part by warning of ways cyber criminals ay attempt to attack businesses and individuals.

Now it seems the company is at it again, this time tackling the botnet behind a recent hacking effort that compromised tow million social network users and cost online advertisers more than $2.7 million per month. By once again partnering with the FBI, as well as A10 Networks and Europol’s Cybercrime Center (EC3), Microsoft managed to stop the botnet, known as ZeroAccess, from doing further damage.

In fact, Microsoft is no working on a preliminary court injunction to direct U.S. ISPs, as well as other groups that control IP addresses, to shut down the botnet’s network. The suit, which was filed in a Texas district court, also acts these groups to preserve any material or content associated with the botnet to help Microsoft’s fight.

Put simply, ZeroAccess affects search engines through the hijacking of a person’s computer. It then redirects that person’s search results, leading them to sites which install malware on the target computer. This allows the cyber criminals behind the botnet to access personal information, while allowing them to commit fraud by charging businesses for advertising clicks.

As of now, ZeroAccess has not been completely disabled, which is why Microsoft has recruited extra help and filed the Texas court injunction. The hope is that the combined technical and legal actions of all involved parties will disable the botnet entirely.