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Security Analysis of SFrame

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Part of the Lecture Notes in Computer Science book series (LNSC,volume 12973)


As people become more and more privacy conscious, the need for end-to-end encryption (E2EE) has become widely recognized. We study the security of SFrame, an E2EE mechanism recently proposed to IETF for video/audio group communications over the Internet. Although a quite recent project, SFrame is going to be adopted by a number of real-world applications. We inspected the original specification of SFrame. We found a critical issue that will lead to an impersonation (forgery) attack by a malicious group member with a practical complexity. We also investigated the several publicly-available SFrame implementations, and confirmed that this issue is present in these implementations.


  • End-to-End Encryption
  • SFrame
  • Authenticated encryption
  • Signature
  • Impersonation

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We are grateful to the SFrame designers (Emad Omara, Justin Uberti, Alex Gouaillard, and Sergio Garcia Murillo) for the fruitful discussion and feedback about our findings. We would like to thank the anonymous reviewers for their insightful comments, and Shiguredo Inc. for helpful discussion about real-world applications of the end-to-end encryption. Takanori Isobe is supported by JST, PRESTO Grant Number JPMJPR2031, Grant-in-Aid for Scientific Research (B)(KAKENHI 19H02141) and SECOM science and technology foundation.

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Correspondence to Ryoma Ito .

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Isobe, T., Ito, R., Minematsu, K. (2021). Security Analysis of SFrame. In: Bertino, E., Shulman, H., Waidner, M. (eds) Computer Security – ESORICS 2021. ESORICS 2021. Lecture Notes in Computer Science(), vol 12973. Springer, Cham.

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