The weak-password problem: Chaos, criticality, and encrypted p-CAPTCHAs

¹ Max-Planck-Institut für Physik komplexer Systeme - Nöthnitzer Straß e 38, D-01187 Dresden, Germany, EU
² Axioma Research - 555 Bryant Street, Palo Alto, CA 94303, USA

^a flach@pks.mpg.de

Received: 4 April 2011
Accepted: 21 July 2011

Abstract

Vulnerabilities related to weak passwords are a pressing global economic and security issue. We report a novel, simple, and effective approach to address the weak-password problem. Building upon chaotic dynamics, criticality at phase transitions, CAPTCHA recognition, and computational round-off errors, we design an algorithm that strengthens the security of passwords. The core idea of our simple method is to split a long and secure password into two components. The first component is memorized by the user. The second component is transformed into a CAPTCHA image and then protected using the evolution of a two-dimensional dynamical system close to a phase transition, in such a way that standard brute-force attacks become ineffective. We expect our approach to have wide applications for authentication and encryption technologies.