They were able to keep track of the Conficker infections by cracking out the algorithm that worm uses to look for the instructions over the Internet and by placing their own sinkhole servers on the domains it is programmed to visit on the Internet. Conficker has many ways to receive these instructions, so the bad guys are still being able to control the PCs, but these sinkhole servers give the researchers one good idea to see that how many machines are actually infected by the worm.

Though Conficker might be the best computer worm known, the PCs continue getting infected by this worm as said by Andre DiMino, who is the co founder of Shadowserver Foundation. He further has said that the trend is increasing definitely and the breaking of 7 million is very much of one landmark event.

Conficker caught the attention first of the security experts in the year of 2008 in November and has received a widespread media attention during the start of year 2009. It has also proved remarkably resilient and is adept at re-infecting the systems even after it has been removed from the computer.