New Privacy Threat on 3G, 4G, and Upcoming 5G AKA Protocols


Mobile communications are used by more than two-thirds of the world population who expect security and privacy guarantees. The 3rd Generation Partnership Project (3GPP) responsible for the worldwide standardization of mobile communication has designed and mandated the use of the AKA protocol to protect the subscribers’ mobile services. Even though privacy was a requirement, numerous subscriber location attacks have been demonstrated against AKA, some of which have been fixed or mitigated in the enhanced AKA protocol designed for 5G.

In this paper, we reveal a new privacy attack against all variants of the AKA protocol, including 5G AKA, that breaches subscriber privacy more severely than known location privacy attacks do. Our attack exploits a new logical vulnerability we uncovered that would require dedicated fixes. We demonstrate the practical feasibility of our attack using low cost and widely available setups. Finally we conduct a security analysis of the vulnerability and discuss countermeasures to remedy our attack.

See our attack in action: demo of our Proof of Concept.

Remark: Our briefing proposal, which covers our attacks on mobile communication protocols presented in this paper, has been accepted at Black Hat USA 2017. Our findings also got some press coverage: ZDnet 1 and 2, The Register 1 and 2, Forbes, NextInpact, EFF, International Business Times,

I also gave an invited talk presenting our findings for the GSMA consortium (most of the worldwide 4G operators) and an invited talk with Ravishankar Borgaonkar at Troopers’17.

Proceedings on Privacy Enhancing Technologies