This post was published 4 years 6 months 20 days ago. Therefore, it may well be out of date. Do not reply on the contents of this post being accurate. The BBC’s article Net criminals shun virus attacks advises that creative criminals have found a way to launch a distributed denial of service attack (DDoS) without directly infecting users’ machines with malware.
One attack seen by Prolexic in May exploited a popular peer-to-peer (P2P) or file-sharing network. By compromising a P2P hub, an attacker was able to bombard a web server from tens of thousands of file-sharers none of whom knew they were taking part in a DDoS.
The only way to avoid taking part in a DDoS attack using this method is to avoid using P2P or BitTorrent clients.