Weaknesses of a Password-Authenticated Key Exchange Protocol between Clients with Different Passwords

  • Shuhong Wang
  • Jie Wang
  • Maozhi Xu
Conference paper

DOI: 10.1007/978-3-540-24852-1_30

Part of the Lecture Notes in Computer Science book series (LNCS, volume 3089)
Cite this paper as:
Wang S., Wang J., Xu M. (2004) Weaknesses of a Password-Authenticated Key Exchange Protocol between Clients with Different Passwords. In: Jakobsson M., Yung M., Zhou J. (eds) Applied Cryptography and Network Security. ACNS 2004. Lecture Notes in Computer Science, vol 3089. Springer, Berlin, Heidelberg

Abstract

A password-authenticated key exchange scheme allows two entities, who only share a memorable password, to authenticate each other and to agree on a cryptographic session key. Instead of considering it in the classic client and server scenarios, Byun et al. recently proposed a password-authenticated key exchange protocol in a cross-realm setting where two clients in different realms obtain a secret session key as well as mutual authentication, with the help of respective servers. In this paper, we first point out that the proposed protocol is not secure, due to the choice of invalid parameters (say, subgroup generator). Furthermore, we show in detail that, even with properly chosen parameters, the protocol has still some secure flaws. We provide three attacks to illustrate the insecurity of the protocol. Finally, countermeasures are also given, which are believed able to withstand our attacks.

Keywords

Password-authenticated key exchange Cross-realm setting Security Dictionary attacks 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Shuhong Wang
    • 1
  • Jie Wang
    • 1
  • Maozhi Xu
    • 1
  1. 1.School of Mathematical SciencesPeking UniversityChina

Personalised recommendations