Security weakness of Android system poses threat to safe mobile use of users. In particular, in case of serious weaknesses, there are even mental and property damages. Although many weaknesses are being resolved by endless analysis and research and development of various security technologies, there are still weaknesses. While the fundamental method to resolve weaknesses is required, it is not easy to find such a method. Therefore, researching on security weaknesses is helpful in developing technologies that can resolve weakness issues. By consistently researching and analyzing security weaknesses, it is expected that development of quick response technology to weaknesses can lead to safer use of Android system.