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Cryptanalysis of the convex hull click human identification protocol

Asghar, HJ, Li, SJ, Pieprzyk, J and Wang, HX (2011) Cryptanalysis of the convex hull click human identification protocol In: 13th International Information Security Conference (ISC 2011), 2010-10-25 - 2010-10-28, Boca Raton, FL, USA.

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Recently a convex hull based human identification protocol was proposed by Sobrado and Birget, whose steps can be performed by humans without additional aid. The main part of the protocol involves the user mentally forming a convex hull of secret icons in a set of graphical icons and then clicking randomly within this convex hull. In this paper we show two efficient probabilistic attacks on this protocol which reveal the user’s secret after the observation of only a handful of authentication sessions. We show that while the first attack can be mitigated through appropriately chosen values of system parameters, the second attack succeeds with a non-negligible probability even with large system parameter values which cross the threshold of usability.

Item Type: Conference or Workshop Item (Conference Paper)
Divisions : Faculty of Engineering and Physical Sciences > Computing Science
Authors :
Asghar, HJ
Li, SJ
Pieprzyk, J
Wang, HX
Date : 2011
DOI : 10.1007/978-3-642-18178-8_3
Contributors :
ContributionNameEmailORCID GmbH,
Related URLs :
Additional Information : The original publication is available at
Depositing User : Symplectic Elements
Date Deposited : 24 Sep 2014 13:15
Last Modified : 31 Oct 2017 14:34

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