Reusable Cryptographic Fuzzy Extractors

By Xavier Boyen.

In 11th ACM Conference on Computer and Communications Security (CCS 2004), pages 82-91. ACM Press, 2004.


We show that a number of recent definitions and constructions of fuzzy extractors are not adequate for multiple uses of the same fuzzy secret — a major shortcoming in the case of biometric applications. We propose two particularly stringent security models that specifically address the case of fuzzy secret reuse, respectively from an outsider and an insider perspective, in what we call a chosen perturbation attack. We characterize the conditions that fuzzy extractors need to satisfy to be secure, and present generic constructions from ordinary building blocks. As an illustration, we demonstrate how to use a biometric secret in a remote error tolerant authentication protocol that does not require any storage on the client's side.


- published paper (PS) (PDF) © ACM
- expanded version (PS) (PDF)
- presentation slides (HTML)


  author = {Xavier Boyen},
  title = {Reusable Cryptographic Fuzzy Extractors},
  booktitle = {ACM Conference on Computer and Communications Security---CCS 2004},
  pages = {82--91},
  publisher = {New-York: ACM Press},
  year = {2004},
  note = {Available at \url{}}

Unless indicated otherwise, these documents are Copyright © Xavier Boyen; all rights reserved in all countries.
Back to Xavier's homepage