Abstract
We cryptanalyse the SIDH-based oblivious pseudorandom function from supersingular isogenies proposed at Asiacrypt’20 by Boneh, Kogan and Woo. To this end, we give an attack on an assumption, the auxiliary one-more assumption, that was introduced by Boneh et al. and we show that this leads to an attack on the oblivious PRF itself. The attack breaks the pseudorandomness as it allows adversaries to evaluate the OPRF without further interactions with the server after some initial OPRF evaluations and some offline computations. More specifically, we first propose a polynomial-time attack. Then, we argue it is easy to change the OPRF protocol to include some countermeasures, and present a second subexponential attack that succeeds in the presence of said countermeasures. Both attacks break the security parameters suggested by Boneh et al. Furthermore, we provide a proof of concept implementation as well as some timings of our attack. Finally, we examine the generation of one of the OPRF parameters and argue that a trusted third party is needed to guarantee provable security.
Original language | English |
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Title of host publication | Advances in Cryptology – ASIACRYPT 2021 |
Subtitle of host publication | 27th International Conference on the Theory and Application of Cryptology and Information Security, Proceedings, Part 1 |
Editors | Mehdi Tibouchi, Huaxiong Wang |
Publisher | Springer |
Pages | 160-184 |
Number of pages | 25 |
Edition | 1 |
ISBN (Electronic) | 9783030920623 |
ISBN (Print) | 9783030920616 |
DOIs | |
Publication status | Published - 1 Dec 2021 |
Event | 27th International Conference on Theory and Application of Cryptology and Information Security, ASIACRYPT 2021 - Virtual, Online Duration: 6 Dec 2021 → 10 Dec 2021 |
Publication series
Name | Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) |
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Volume | 13090 LNCS |
ISSN (Print) | 0302-9743 |
ISSN (Electronic) | 1611-3349 |
Conference
Conference | 27th International Conference on Theory and Application of Cryptology and Information Security, ASIACRYPT 2021 |
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City | Virtual, Online |
Period | 6/12/21 → 10/12/21 |
Bibliographical note
Funding Information:Acknowledgments. We would like to thank Dan Boneh, Jesús Javier Chi Domínguez, Luca De Feo, Enric Florit, Dmitry Kogan and Simon Masson for fruitful discussions. Péter Kutas, Simon-Philipp Merz and Christophe Petit were supported by EPSRC and the UK government as part of the grant EP/S01361X/1 for Péter Kutas and Christophe Petit and the grant EP/P009301/1 for Simon-Philipp Merz. Further, Péter Kutas was supported by the Ministry of Innovation and Technology and the National Research, Development and Innovation Office within the Quantum Information National Laboratory of Hungary.
Publisher Copyright:
© 2021, International Association for Cryptologic Research.
ASJC Scopus subject areas
- Theoretical Computer Science
- General Computer Science