[en] Currently, the Simple Password-Based Encrypted Key Exchange (SPAKE2) protocol of Abdalla and Pointcheval (CT-RSA 2005) is being considered by the IETF for standardization and integration in TLS 1.3. Although it has been proven secure in the Find-then-Guess model of Bellare, Pointcheval and Rogaway (EUROCRYPT 2000), whether it satisfies some notion of forward secrecy remains an open question.
In this work, we prove that the SPAKE2 protocol satisfies the so-called weak forward secrecy introduced by Krawczyk (CRYPTO 2005).
Furthermore, we demonstrate that the incorporation of key-confirmation codes in SPAKE2 results in a protocol that provably satisfies the stronger notion of perfect forward secrecy. As forward secrecy is an explicit requirement for cipher suites supported in the TLS handshake, we believe this work could fill the gap in the literature and facilitate the adoption of SPAKE2 in the recently approved TLS 1.3.
Research center :
Interdisciplinary Centre for Security, Reliability and Trust (SnT) > Applied Security and Information Assurance Group (APSIA)
Disciplines :
Computer science
Author, co-author :
Lopez Becerra, José Miguel ; University of Luxembourg > Interdisciplinary Centre for Security, Reliability and Trust (SNT)
Ostrev, Dimiter ; University of Luxembourg > Interdisciplinary Centre for Security, Reliability and Trust (SNT)
Skrobot, Marjan
External co-authors :
no
Language :
English
Title :
Forward Secrecy for SPAKE2
Publication date :
25 October 2018
Event name :
The 12th International Conference on Provable Security
Event place :
Jeju, South Korea
Event date :
25-10-2018 to 28-10-2018
Audience :
International
Main work title :
Provable Security
Editor :
Baek, Joonsang
Willy, Susilo
Publisher :
Springer International Publishing
ISBN/EAN :
978-3-030-01446-9
Pages :
366-384
Peer reviewed :
Peer reviewed
Focus Area :
Security, Reliability and Trust
FnR Project :
FNR8293135 - A Theory Of Matching Sessions, 2014 (01/05/2015-30/04/2018) - Peter Y. A. Ryan
