The FBI warns of an Internet doomsday to all PC users infected with the malware labeled as DNS Changer. They have until July 9 to disinfect their Windows PCs and Macs. After all these malware brouhaha, the FBI will prevent infected PCs from Internet access with just one switch. A malware application, DNS Changer replaces the valid IP addresses used for both primary and secondary DNS servers with the ones chosen by the attacker. Once it’s done, any requested name resolution will be forwarded to the attacker’s DNS servers. Depending on the situation, the DNS servers of the attackers could reply with either correct or incorrect records of DNS. The whole game plan revolves around deception. What the attackers really need are requests of name resolution for valid Web sites where they have produced malicious copies of. If the attackers’ DNS servers would be able to respond appropriately for most of the name resolution requests, most PC users aren’t going to be suspicious about anything. The DNS Changer or Trojan.Flush.M is notorious in targeting Mac OS X and Windows OS. Experts are also saying that DNS Changer has influenced Apple to advise Mac users about using antivirus software. Throughout its existence, DNS Changer has already received an intense scrutiny. When it deals with malware propagation, security analysts keep their eyes wide open and learn side by side with the malware coders what actually works and what fails. PC users can visit the DNS Changer Check-Up site to check if they’re infected. It can check their PCs DNS resolution without having to install extra software. For users with infected PCs, there is a list of anti-virus software given by the DNS Changer Working Group that can help them fix the problem. Moreover, there is a repair tool specifically designed for DNS Changer which is offered by Avira.