Privacy of users in P2P networks goes far beyond their current usage and is a
fundamental requirement to the adoption of P2P protocols for legal usage. In a
climate of cold war between these users and anti-piracy groups, more and more
users are moving to anonymizing networks in an attempt to hide their identity.
However, when not designed to protect users information, a P2P protocol would
leak information that may compromise the identity of its users. In this paper,
we first present three attacks targeting BitTorrent users on top of Tor that
reveal their real IP addresses.