Cryptology ePrint Archive: Report 2009/430

One-time-password-authenticated key exchange

Kenneth G. Paterson and Douglas Stebila

Abstract: To reduce the damage of phishing and spyware attacks, banks, governments, and other security-sensitive industries are deploying one-time password systems, where users have many passwords and use each password only once. If a single password is compromised, it can be only be used to impersonate the user once, limiting the damage caused. However, existing practical approaches to one-time passwords have been susceptible to sophisticated phishing attacks.

We give a formal security treatment of this important practical problem. We consider the use of one-time passwords in the context of password-authenticated key exchange (PAKE), which allows for mutual authentication, session key agreement, and resistance to phishing attacks. We describe a security model for the use of one-time passwords, explicitly considering the compromise of past (and future) one-time passwords, and show a general technique for building a secure one-time-PAKE protocol from any secure PAKE protocol. Our techniques also allow for the secure use of pseudorandomly generated and time-dependent passwords.

Category / Keywords: cryptographic protocols / one-time passwords, key exchange, protocols, public-key cryptography

Date: received 3 Sep 2009, last revised 3 Sep 2009

Contact author: douglas at stebila ca

Available format(s): PDF | BibTeX Citation

Version: 20090904:054832 (All versions of this report)

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