A newly discovered malware called Vigilante is installed when victims download and run what they believe to be counterfeit software or games.
Once inside the system, the malware reports the file name that has been executed to an attacker-controlled server, along with the IP address of the victim’s computer.
Towards the end, Vigilante modifies the victims’ computers so that they can no longer access thepiratebay.com and 1,000 other pirate sites.
Specifically, the malware updates Hosts, a file that pairs one or more domain addresses to different IP addresses.
By assigning the domains to the local host, the malware ensures that the computer can no longer access the pages, and the only way to reverse the block is to edit the Hosts file to remove the entries.
Many of the trojanized executables are digitally signed using a fake code-designing tool.
The signatures consist of a series of randomly generated 18-character uppercase and lowercase letters. The validity of the certificate began on the day of availability of the files and ends in 2039.
Properties of the executable files do not match the filename.
The good thing is that Vigilante is not good at perpetuating itself, which means that it has no way to stay installed. Users who have been infected just need to edit their Hosts file to get disinfected.
For more information, read the original story in Arstechnica.