Using Provenance Patterns to Vet Sensitive Behaviors in Android Apps

Summary. We propose Dagger, a lightweight system to dynamically vet sens-itive behaviors in Android apps. Dagger avoids costly instrumentation of virtual machines or modifications to the Android kernel. Instead, Dagger reconstructs the program semantics by tracking provenance relationships and observing apps’ runtime interactions with the phone platform. More specifically, Dagger uses three types of low-level execution information at runtime: system calls, Android Binder transactions, and app process details. System call collection is performed via Strace [7], a low-latency utility for Linux and other Unix-like systems. Binder transactions are recorded by accessing Binder module logs via sysfs [8]. App pro-cess details are extracted from the Android /proc file system [6]. A data proven-ance graph is then built to record the interactions between the app and the phone system based on these three types of information. Dagger identifies behaviors by matching the provenance graph with the behavior graph patterns that are previ-ously extracted from the internal working logic of the Android framework. We evaluate Dagger on both a set of over 1200 known malicious Android apps, and a second set of 1000 apps randomly selected from a corpus of over 18,000 Google Play apps. Our evaluation shows that Dagger can effectively vet sensitive be-haviors in apps, especially for those using complex obfuscation techniques. We measured the overhead based on a representative benchmark app, and found that both the memory and CPU overhead are less than 10%. The runtime overhead is less than 63%, which is significantly lower than that of existing approaches.