Towards detecting device fingerprinting on iOS with API function hooking

Device fingerprinting is a technique that got popular at the end of the 90s by websites, to identify and track users. One of the biggest drivers behind such practices are advertising companies to identify users interests to personalize ads. From a user’s perspective, this, of course, raises privacy concerns. While device fingerprinting and its detection has been extensively studied in the context of web browsing, little research has been conducted on device fingerprinting in mobile apps and especially iOS apps. In this paper, we capture the current state of device fingerprinting in iOS apps, and explore possible approaches for fingerprinting detection on mobile devices using static and dynamic app analysis techniques. Finally, we present a first heuristic approach for automatic behavior-based fingerprinting detection on iOS only using spatial and temporal context of relevant API-calls.