P2P File-Sharing in Hell: Exploiting BitTorrent Vulnerabilities to Launch Distributed Reflective DoS Attacks

In this paper, we demonstrate that the BitTorrent protocol family is vulnerable to distributed reflective denial-of-service (DRDoS) attacks. Specifically, we show that an attacker can exploit BitTorrent protocols (Micro Transport Protocol (uTP), Distributed Hash Table (DHT), Message Stream Encryption (MSE))and BitTorrent Sync (BTSync) to reflect and amplify traffic from peers. We validate the efficiency, robustness and evadability of the exposed BitTorrent vulnerabilities in a P2P lab testbed. We further substantiate the lab results by crawling more than 2.1 million IP addresses over Mainline DHT (MLDHT) and analyzing more than 10,000 BitTorrent handshakes. Our experiments reveal that an attacker is able to exploit BitTorrent peers to amplify the traffic up to a factor of 50 times and in case of BTSync up to 120 times. Additionally, we observe that the most popular BitTorrent clients are the most vulnerable ones.