Website fingerprinting is a dangerous attack against users of systems for online privacy like Tor
Website Fingerprinting
Anonymity systems like Tor provide privacy for journalists, activists, businesses, military, and regular users. But an attacker can break those privacy protections by eavesdropping on the encrypted link between the user and Tor and using website fingerprinting to figure out which site the user is going to. Center Director Matt Wright is part of a project funded by National Science Foundation to work with the Tor Project to develop and deploy a lightweight defense against these attacks.