Password exhaustion: Predicting the end of password usefulness

Luke St. Clair, Lisa Johansen, William Enck, Matthew Pirretti, Patrick Traynor, Patrick McDaniel, Trent Jaeger

Research output: Chapter in Book/Report/Conference proceedingConference contribution

29 Scopus citations


Passwords are currently the dominant authentication mechanism in computing systems. However, users are unwilling or unable to retain passwords with a large amount of entropy. This reality is exacerbated by the increasing ability of systems to mount offline attacks. In this paper, we evaluate the degree to which the previous statements are true and attempt to ascertain the point at which passwords are no longer sufficient to securely mediate authentication. In order to demonstrate this, we develop an analytical model for computation to understand the time required to recover random passwords. Further, an empirical study suggests the situation is much worse. In fact, we found that past systems vulnerable to offline attacks will be obsolete in 5-15 years, and our study suggests that a large number of these systems are already obsolete. We conclude that we must discard or fundamentally change these systems, and to that effect, we suggest a number of ways to prevent offline attacks.

Original languageEnglish (US)
Title of host publicationInformation Systems Security - 2nd International Conference, ICISS 2006, Proceedings
EditorsAditya Bagchi, Vijayalakshmi Atluri
PublisherSpringer Verlag
Number of pages19
ISBN (Print)9783540689621
StatePublished - 2006
Event2nd International Conference on Information Systems Security, ICISS 2006 - Kolkata, India
Duration: Dec 19 2006Dec 21 2006

Publication series

NameLecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
Volume4332 LNCS
ISSN (Print)0302-9743
ISSN (Electronic)1611-3349


Other2nd International Conference on Information Systems Security, ICISS 2006

All Science Journal Classification (ASJC) codes

  • Theoretical Computer Science
  • General Computer Science


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