Kelihos Botnet dismantled by Microsoft and Kaspersky Lab - 
Kelihos botnet was famous for shooting up 3.8 billion spam e-mails every day. It was recently taken down by a joint movement from Microsoft and Kaspersky Lab.
According to reports, it was only four months ago that it was controlled and managed by a software developer who formerly worked for an unidentified antivirus firm. Microsoft updated their statement yesterday in a civil lawsuit. Microsoft was on their tail since several months working on dismantling the Kelihos botnet.
As a recent success they have found out that the person responsible behind the site's overall coding and operation of the Kelihos botnet. It was Andrey N. Sabelnikov – a Russian citizen identified in Microsoft's civil suit over this issue.
So what was Kelihos Botnet?
Like all other Botnets that are simply groups or organization of infected "zombie" computers all around the globe that can be manipulated and controlled by a single person or an entire group. These are usually rented out to the highest bidder to perform tasks like sending out massive volumes of spam or hitting MNC companies with DDOS attacks. These computers are thoroughly infected in a variety of ways, from backdoor trojans to replicating viruses. The source simply comes from downloading illegal content, such as cracks, keygens or by a simple method of installing fake(pirated) copies of antivirus products by users.
Thanks to Kelihos Botnet, the quest for fake antivirus scam has reached its success point over the recent years as users have become more aware of the need for online security. This awareness often has a bad backdoor - users are completely unaware at the same time that they are inviting the threats to disrupt their safe computing.
How did Kelihos Botnet work?
Hackers from Kelihos Botnet used advertisements that appeared to show a scan of the user’s PC and that it was infected by a virus – and then offering them a software anti-virus solution to fix the issue. Some of them managed users into paying for fake antivirus content that was effectively useless, whilst others – as alleged in this case – gave the software away for free only to install some real viruses or trojans on the user’s PC.
So as Microsoft reported, either way Kelihos Botnet was designed to harm the innocent users.