Circuit Fingerprinting-Unmasking Tor Users without Decrypting Traffic.

Image source : https://people.csail.mit.edu/devadas/pubs/circuit_finger.pdf

Well.., Looks like the reliability of Tor Is Peeling off like an onion. Tor is no more safe, proved again. A team of security researchers from Massachusetts Institute of Technology (MIT) has developed digital attacks that can be used to unmask Tor hidden services in the Deep Web with a high degree of accuracy.

Circuit Fingerprinting Attack

A new vulnerability was found in the Tor's Guard gateway which can be exploited to detect whether a user is accessing one of Tor's hidden services. Tor's Guard Gateways could be masqueraded and the packets coming from the user could be made to travel through attacker’s malicious ‘setup’ node acting as an Entry node. This includes a series of passive attacks which allows spies to unmask Tor users with 88 percent accuracy even without decrypting the Tor traffic. The researchers described this technique as "Circuit Fingerprinting,"

Passive De-Anonymization Of Tor Users

This new alternative approach not only tracks the digital footprints of Tor users but also reveals exactly which hidden service the user was accessing; just by analyzing the traffic data and the pattern of the data packets. According to the research team, Tor exhibits finger-printable traffic patterns that allow an attacker to efficiently and accurately identify and correlate circuits involved in the communication with hidden services. So an attacker would be adopting the technique of identifying suspicious circuits with high confidence instead of monitoring every circuit. The technique nowhere breaks down the layered encrypted route of Tor network, so being encrypted doesn't make your identity anonymous from others.

Tor-Is it hacked or becoming unreliable? 

Tor is considered to be one of the cheapest and simplest ways to ensure Anonymity while accessing the Internet. With the time and a couple of successful breaches in the past, it seems that the reliability of Tor is questioned. However, the Tor project leader Roger Dingledine raises a question to the researchers asking about the genuineness of the accuracy that the Traffic fingerprinting technique delivers. According to the MIT News article, the fix was suggested to Tor project representatives, who may add it to a future version of Tor.

The full paper can be found at https://people.csail.mit.edu/devadas/pubs/circuit_finger.pdf

Tor Alternative?

Yes, there are better alternatives to Tor. One such promising Tor Alternative is HORNET- High-speed Onion Routing at the Network Layer. I have written a detailed post about HORNET before. It can be read from the below link.

HORNET: Ultra High Speed & Secure TOR Alternative