Research And Realization On The Prevention And Detection Technology Of Malicious Behaviors Of SMS On Android Platform

Since the launch of the Android system in2007, applications on such platform have been developed by leaps and bounds, accompanied by an overflow of malicious software. Today the Android system has become the main target of hackers. Among all the attacks, cell phone users are aggressively antagonistic to the malicious behaviors of sms. What’s more, with the growing popularity of cell phone payment applications, the message verification code is in wide use. Therefore, the study of the security of Android message is of great importance to users’own interests.Firstly, the security mechanism of Android system as well as the receiving and sending process of short message is researched in this paper. Therefore with the knowledge of principles of short message, its potential risk of the messaging process are found.Secondly, with deeper analyzing of the realization and working principle of the way that malicious message got uses’private data and charging maliciously, this paper proposes two static methods to prevent the background sending malicious message. On the one hand, a signature detection method is used to find out whether an application has been injected by malicious code. In this way, we can detect users installing malicious applications in the first place. On the other hand, APIs of Android source code, which are usually manipulated by malicious application are modified to detect malicious applications. In this paper, by changing the source code, the system would popup a window whenever a background application secretly calls the SMS API functions. And it would to let the user decide whether the message should be sent. Thus, this method could prevent from background sending message without the users’awareness which led to malicious behaviors.Lastly, because that the static detection methods lack flexibility if the apps have been installed on the system, a message detection system is designed and realized to monitor and detect the messaging process in order to find prevent malicious softwares from sending and blocking messages and charging maliciously. Users could check detailed information of messaging and create and modify a trust list of softwares with this system. So whenever a background message is sent, the system could compare the owner of the message with the trust list. If the software which sends the message was not on the trust list, it would be marked as a suspicious message, then the user would be reminded to check the message. When the cell phone receives a message, the system would get this message with the highest priority, preventing the message from interception. At the same time, users could compare the message with the internal message database. Therefore, messages which are not in the database will be showed, to find out whether the sms has been intercepted. Lastly, the GUI of this system is showed, and the system is also certificated its usefulness by appropriate tests.