Security researchers warn against downloading the Windows 7 RC from torrent websites, as a version with a built-in trojan is circulating the Internet. Damballa claims thousands of users have become part of a botnet after downloading an illegal version of Windows 7.
According to researchers at Damballa, attackers hid a Trojan inside of pirated copies of the operating system and began circulating them on BitTorrent sites. Damballa reported that it shut down the botnet's command and control server May 10, but by that time infection rates had risen as high as 552 users per hour.
"Since the pirated package was released on April 24th, my best guess is that this botnet probably had at least 27,000 successful installs prior to our takedown of its CnC [command and control] on May 10th," said Tripp Cox, vice president of engineering at Damballa.