RAPTOR: Routing Attacks on Privacy in Tor

Authors: Yixin Sun, Anne Edmundson, Laurent Vanbever, Oscar Li, Jennifer Rexford, Mung Chiang, and Prateek Mittal
Proceedings of the 24th USENIX Security Symposium


The Tor network is a widely used system for anonymous communication. However, Tor is known to be vulnerable to attackers who can observe traffic at both ends of the communication path. In this paper, we show that prior attacks are just the tip of the iceberg. We present a suite of new attacks, called Raptor, that can be launched by Autonomous Systems (ASes) to compromise user anonymity. First, AS-level adversaries can exploit the asymmetric nature of Internet routing to increase the chance of observing at least one direction of user traffic at both ends of the communication. Second, AS-level adversaries can exploit natural churn in Internet routing to lie on the BGP paths for more users over time. Third, strategic adversaries can manipulate Internet routing via BGP hijacks (to discover the users using specific Tor guard nodes) and interceptions (to perform traffic analysis). We demonstrate the feasibility of Raptor attacks by analyzing historical BGP data and Traceroute data as well as performing real-world attacks on the live Tor network, while ensuring that we do not harm real users. In addition, we outline the design of two monitoring frameworks to counter these attacks: BGP monitoring to detect control-plane attacks, and Traceroute monitoring to detect data-plane anomalies. Overall, our work motivates the design of anonymity systems that are aware of the dynamics of Internet routing.



	isbn = {978-1-931971-232},
	year = {2015},
	booktitle = {Proceedings of the 24th USENIX Security Symposium},
	type = {Conference Paper},
	author = {Sun, Yixin and Edmundson, Anne and Vanbever, Laurent and Li, Oscar and Rexford, Jennifer and Chiang, Mung and Mittal, Prateek},
	language = {en},
	address = {Berkeley, CA},
	publisher = {USENIX Association},
	title = {RAPTOR: Routing Attacks on Privacy in Tor},
	PAGES = {271 - 286},
	Note = {24th USENIX Security Symposium (USENIX Security 2015); Conference Location: Washington, DC, USA; Conference Date: August 12-14, 2015; See also: http://e-citations.ethbib.ethz.ch/view/pub:163104.}

Research Collection: 20.500.11850/103894