PhoneCheck: App-level protection against eavesdropping on Android

With increased popularity of mobile devices, recent years have seen a burgeoning adoption of smartphones in telecommunication industry. However, eavesdroppers covertly installed in smartphones bring tremendous risk to the user privacy. To mitigate such threat, we propose a defending mechanism that provides real-time protection in app-level. Our method does not need a root or system privilege, as well as any modification of the OS or apps. We summarize the eavesdropping categories, and then develop a tool named PhoneCheck, which performs analysis on permissions, side channels and behaviors. PhoneCheck will detect the suspicious processes or calls and block them. To demonstrate the effectiveness of PhoneCheck, we analyze its accuracy rate, FPR and TPR in detecting the two kinds of eavesdroppers. Our experimental studies show that this new technique is effective in defeating all known phone attacks on Android platform and introduces small performance overhead.