Repackage-Proofing Android Apps

TL;DR: A technique is proposed that builds a reliable and stealthy repackage-proofing capability into Android apps and injects a failure in the form of delayed malfunctions, making it difficult to trace back once repackaging is detected.

Abstract: App repackaging has become a severe threat to theAndroid ecosystem. While various protection techniques, such aswatermarking and repackaging detection, have been proposed, adefense that stops repackaged apps from working on user devices, i.e., repackage-proofing, is missing. We propose a technique thatbuilds a reliable and stealthy repackage-proofing capability intoAndroid apps. A large number of detection nodes are insertedinto the original app without incurring much overhead, each iswoven into the surrounding code to blur itself. Once repackagingis detected, a response node injects a failure in the form ofdelayed malfunctions, making it difficult to trace back. Theresponse nodes and detection nodes form high-degree connectionsand communicate through stealthy communication channels, suchthat upon detection several of the many response nodes areselected stochastically to take actions, which further obfuscatesand enhances the protection. We have built a prototype. Theevaluation shows that the technique is effective and efficient.