Abstract:

A privacy protection system based on Hook technology was designed and implemented to address the problem of user privacy leakage caused by malicious applications in Android.The system consists of three modules:application classification module,privacy information management module and collusion attack management module.The application classification module constructs classification model by using permission feature vectors and then classifies mobile applications into malicious applications and normal applications.The privacy information management module hooks all privacy-related application programming interfaces (API) based on Hook technology and then intercepts malicious applications by returning false data or empty data.The collusion attack management module hooks all inter-application communication channels and then intercepts corresponding communication contents by using the permission rules of collusion attack.Finally,the proposed privacy protection scheme on Android virtual machine was implemented to prove and its feasibility and effectiveness were proved.In addition,the system can intercept application behaviors of breaching privacy in real time with less memory,which does not need to modify Android system and applications.

Key words: privacy protection, Android platform, Hook technology, collusion attack, permission management