FPFlow: Detect and Prevent Browser Fingerprinting with Dynamic Taint Analysis

Browser fingerprinting is a practical user tracking technology widely adopted by many real-world websites to potentially track users' browsing behaviors. By collecting information such as screen resolution, user agent, and WebGL rendered data, the tracker can generate a unique identifier for users without their knowledge, leading to a severe violation of user privacy. Therefore, an effective detection and defense technology for browser fingerprinting is needed to protect user privacy. In this paper, we proposed FPFlow, a dynamic JavaScript taint analysis framework to detect and prevent browser fingerprinting. FPFlow monitors the whole process of browser fingerprinting, including collecting information, generating fingerprinting, and sending it to the remote server. We evaluated FPFlow on TRANCO top 10,000 websites. Our experiments showed that our framework could effectively detect browser fingerprints. We found 66.6% of the websites performing fingerprinting and revealed how browser fingerprinting is applied in real-world websites. We also showed that FPFlow could prevent browser fingerprinting with an acceptable overhead.