Hackers of India

Understanding IMSI Privacy

 Swapnil Udar   Ravishankar Borgaonkar 


Presentation Material


It is said that 80% of the world’s population now has a mobile phone. They use mobile devices to make calls, send SMS messages, and to access the Internet via the cellular network infrastructure. End-users carrying mobile phones 24 hours trust cellular network operators and believe that the provided mobile communication link is secure.

However, on the other hand, mobile operators, device manufacturers, OS providers, and baseband suppliers do little to provide best security and privacy features to them. In particular, security capabilities of mobile communications are not shown to the end-users. Hence, it is easy for malicious attackers to mount subsequent attacks using IMSI catcher equipments. Further some hidden features, for example ‘silent SMS’, are supported in currently used mobile telephony systems but not notified to the end-users when in use. Attackers or illegitimate agencies exploit this weakness to track user movements regularly without the user’s consent.

In this talk, we address these long-standing issues by developing a low-cost, easy-to-use privacy framework based on Android OS. We demonstrate our effort to build an ideal way to protect user privacy. A live demo of framework detecting hidden (in ) security features of mobile communication system will be provided.