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arXiv · 1307.8186

An Oblivious Password Cracking Server

Aureliano Calvo·Ariel Futoransky·Carlos Sarraute
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Abstract

Building a password cracking server that preserves the privacy of the queries made to the server is a problem that has not yet been solved. Such a server could acquire practical relevance in the future: for instance, the tables used to crack the passwords could be calculated, stored and hosted in cloud-computing services, and could be queried from devices with limited computing power. In this paper we present a method to preserve the confidentiality of a password cracker---wherein the tables used to crack the passwords are stored by a third party---by combining Hellman tables and Private Information Retrieval (PIR) protocols. We provide the technical details of this method, analyze its complexity, and show the experimental results obtained with our implementation.

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Aureliano Calvo, Ariel Futoransky, Carlos Sarraute. 2013-07-31. An Oblivious Password Cracking Server. https://arxiv.org/abs/1307.8186

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