A collaborative framework for generating probabilistic contracts

We propose a collaborative framework for generating probabilistic contracts for Android smartphones aimed at detecting repackaged applications. To this end, a network of users sends to the application server the sequences of actions that represent the usage profile of the application. Then, the application server generates a contract from this set of traces. Contracts are represented through clustered probabilistic automata. At run-time, a monitoring system on the smartphone verifies the compliance of the running application against the contract through the Pearson´s Chi Squared test. In the preliminary tests, the proposed framework has been able to detect repackaged applications whose behavior is strongly similar to the original application but hide malware.