SignalCookie: Discovering Guard Relays of Hidden Services in Parallel
Muqian Chen, Xuebin Wang, Tingwen Liu, Jinqiao Shi, Zelin Yin, Binxing Fang · 2019
In this paper, we propose the SignalCookie attack which can reveal guard relays of multiple hidden services in parallel. The key insight of our method is utilizing Rendezvous Cookie and circuit watermark to deliver the hidden services' identifiers to our controlled relays. By conducting the attack in parallel, the speed of our method increases about 11.6 times compared with the previous work, so that we can continually monitor the guard relays of 13604 hidden services for 7 months. And we have an interesting finding by analyzing the distribution of hidden services binding on each guard relays. The distribution is quite uneven, that only 20% of guard relays serve about 89.32% hidden services. These guard relays would bind all hidden services at least one time in about 17 months. At last, we analyze several security problems aggravated by the uneven distribution, and find that just one corrupt guard relay may cause hundreds of hidden services being de-anonymized or eclipsed.