Taming Mr Hayes: Mitigating signaling based attacks on smartphones

Malicious injection of cellular signaling traffic from mobile phones is an emerging security issue. The respective attacks can be performed by hijacked smartphones and by malware resident on mobile phones. Until today there are no protection mechanisms in place to prevent signaling based attacks other than implementing expensive additions to the cellular core network. In this work we present a protection system that resides on the mobile phone. Our solution works by partitioning the phone software stack into the application operating system and the communication partition. The application system is a standard fully featured Android system. On the other side, communication to the cellular network is mediated by a flexible monitoring and enforcement system running on the communication partition. We implemented and evaluated our protection system on a real smartphone. Our evaluation shows that it can mitigate all currently known signaling based attacks and in addition can protect users from cellular Trojans.