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	Cryptographic analysis of messaging protocols: a spotlight on Telegram

Host: Prof. Marc Langheinrich

Friday

13.06

USI Campus EST, Room C1.03

08:45 - 09:30


	Lenka Mareková ETH Zurich

Abstract:Telegram has grown from a niche messaging application favoured by users in fairly specific contexts to a widely popular platform and the subject of major news headlines. Throughout this time, Telegram has continued to rely on a set of non-standard and custom-made protocols to secure the communication between Telegram clients and servers. Since very little was understood about their security, this made it an attractive target for cryptanalysis. In this talk, I will explain how we analysed these protocols from a cryptographic perspective. I will describe our process as well as the results, which came in the form of attacks, both at the implementation and the protocol level, as well as security proofs for fixed versions of the protocols. I will conclude by distilling a few broader lessons that can be taken away from this work.

Biography: Lenka Mareková is currently a postdoc in the Applied Cryptography Group at ETH Zurich, focusing on the analysis and design of secure messaging protocols. She obtained her PhD in the Information Security Group at Royal Holloway, University of London under the supervision of Martin R. Albrecht.