The FBI has actually done you a favor.
Instead of shutting the servers responsible for the DNS Changer botnet down, they have kept them up and running. Why? Millions of computer users were infected by this trojan, and shutting these servers down would instantly result in loss of internet access for those millions still infected.
This is because of the way the malware writers set up the botnet. DNS Changer trojan reported back to the servers the gang used to run/own; infected systems would be directed here for all internet access, and then would go out to wherever the user wanted to go. Unfortunately, this also meant the infected system was, for all practical purposes, owned by this gang, for as long as they continued to operate. They made their money on a pay-per-click basis based on fraudulent advertising revenue for each system infected, so every system user unknowingly and unwittingly made them money as they surfed the internet.
When the FBI and others arrested the members responsible, they also took possession and control of these servers. This happened on November 9th, 2011. The DNS Changer organization had been in operation for more than five years at that point, beginning sometime in 2007.
Owning a system on the internet that is not yours is very profitable; there are myriad ways of making money off the data stolen, identity theft, etc. In hackers lingo, you are pwnd if this happens to you.
It is up to the user to check for infection, and remove/clean it if found. Tools and instructions are provided @ http://www.dcwg.org on how to check and clean if necessary.
So, in short, use the above site to see if you are infected. If you are not, you have nothing to worry about. If, however, you are infected, and you are not comfortable in cleaning an infected system, take it to a reputable local computer shop you know and trust. But get this done sometime before July 9th, 2012.
The FBI and the court system has extended the cutoff date for the cessation of the DNS Changer servers operation twice already; one of the latest estimates say that some 3,000,000 systems are still infected as of two days ago. If these servers were shut down today, that would mean three million users suddenly without internet access. Some of those users are in a corporate environment, alas.
Note: This post was edited by its original author to fix incorrect link on 05/04/2012 at 5:40 PM PT
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