OneSwarm is a system for anonymous p2p file sharing in use by thousands of peers. It aims to provide Onion Routing-like privacy and BitTorrent-like performance. We demonstrate several flaws in OneSwarm’s design and implementation through three different attacks available to forensic investigators. First, we prove that the current design is vulnerable to a novel timing attack that allows just two attackers attached to the same target to determine if it is the source of queried content. When attackers comprise 15% of OneSwarm peers, we expect over 90% of remaining peers will be attached to two attackers and therefore vulnerable. Thwarting the attack increases OneSwarm query response times, making them longer than the equivalent in Onion Routing. Second, we show that OneSwarm’s vulnerability to traffic analysis by colluding attackers is much greater than was previously reported, and is much worse than Onion Routing. We show for this second attack that when investigators comprise 2...