Check out the new USENIX Web site.

Home About USENIX Events Membership Publications Students
Security '01 Abstract

Dos and Don'ts of Client Authentication on the Web

Kevin Fu, Emil Sit, Kendra Smith, Nick Feamster, MIT Laboratory for Computer Science

Abstract

Client authentication has been a continuous source of problems on the Web. Although many well-studied tech-niques exist for authentication, Web sites continue to use extremely weak authentication schemes, especially in non-enterprise environments such as store fronts. These weaknesses often result from careless use of authentica-tors within Web cookies. Of the twenty-seven sites we investigated, we weakened the client authentication on two systems, gained unauthorized access on eight, and extracted the secret key used to mint authenticators from one. We provide a description of the limitations, require-ments, and security models specific to Web client authen-tication. This includes the introduction of the interrog-ative adversary, a surprisingly powerful adversary that can adaptively query a Web site. We propose a set of hints for designing a secure client authentication scheme. Using these hints, we present the design and analysis of a simple authentication scheme secure against forgeries by the interrogative adversary. In conjunction with SSL, our scheme is secure against forgeries by the active adversary.
  • View the full text of this paper in HTML, PDF, and PostScript.
    The Proceedings are published as a collective work, © 2001 by the USENIX Association. All Rights Reserved. Rights to individual papers remain with the author or the author's employer. Permission is granted for the noncommercial reproduction of the complete work for educational or research purposes. USENIX acknowledges all trademarks within this paper.

  • If you need the latest Adobe Acrobat Reader, you can download it from Adobe's site.

  • To become a USENIX Member, please see our Membership Information.

?Need help? Use our Contacts page.

Last changed: 30 Apr 2002 ml
Technical Program
Security '01 Home
USENIX home