Attacks on Message Stream Encryption
Billy Bob Brumley, Jukka Valkonen · 2008
Abstract. Message Stream Encryption (MSE) provides obfuscation, data confidentiality, and limited authentication to BitTorrent clients. Although obfuscation of header and payload data was the main design goal of MSE, users understandably still expect data confidentiality and authentication from their BitTorrent clients. In this paper, we present numerous attacks on the MSE protocol itself, independent of clients. We then test many popular BitTorrent clients for vulnerability to these attacks, resulting in a number of serious vulnerabilities in popular clients. These results are timely and significant due to the high penetration rate of BitTorrent clients. Key words: BitTorrent, peer-to-peer protocols, stream ciphers, man-in-the-middle attacks. 1