Researchers cancel session on ‘exposing Tor users’ on Black Hat

Two security researchers from Carnegie Mellon University cut a talk at the Black Hat conference in which they were supposed to show how to identify Tor users. A university committee did not approve.

The session that the two researchers wanted to hold at the Black Hat USA 2014 hacker conference would reveal a “cheap” method to undo the anonymization of Tor users and hidden web servers. That method would only cost a few thousand euros in equipment.

A nomination announcement spoke of shortcomings in the design and implementation of the Tor anonymization network, but the researchers did not disclose further details. However, the university where the two security researchers work has banned the session after being urged by the Software Engineering Institute.

It is unclear why the presentation was deleted. Roger Dingledine, one of the creators of the Tor software and a member of the Tor organization, says they knew nothing about the session deletion. The developer would have several questions for the duo. However, the Tor developer hopes that they will be able to release more information about possible vulnerabilities in the Tor software in collaboration with CERT.

The volunteer-run Tor network allows users to browse the web anonymously. Various encryption methods are used for this. The NSA, among others, is very interested in users of the Tor network and tries to identify them through detours, for example by exploiting browser bugs.