About 12 million Internet users per month were infected by downloading material from the torrent files. Almost one-third of the 800 torrent sites served malware on the users machine between June and August 2015. The profit of this lucrative business allowed crooks to earn more than 70 million dollars. Most torrent websites earn money by selling ads to malicious advertisers ho serve malware that criminal organizations use to harvest users’ data to resell on the black market. Most of the computers are infected via malicious ads spread through the torrent websites, the ads redirect victims to websites hosting malicious exploit kits.”]
Source: http://securityaffairs.co/wordpress/42768/cyber-crime/torrent-websites-malware.html