How to Break CaptchaStar

Thomas Gougeon, Patrick Lacharme

Abstract

Most of web sites adopt a Captcha system to distinguish malicious software from humans. This paper proposes an attack on a recent interactive image-based Captcha scheme, called CaptchaStar. The CaptchaStar was designed to be more secure and user friendly than existing solutions, however, as we show in this paper, it fails to meet these goals Nevertheless, the presented attack is very efficient, with a success rate for the attacker of 96% on the on-line version proposed by the authors. Moreover, the modification of CaptchaStar parameters (as noise addition) does not prevent our attack.

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Paper Citation


in Harvard Style

Gougeon T. and Lacharme P. (2018). How to Break CaptchaStar.In Proceedings of the 4th International Conference on Information Systems Security and Privacy - Volume 1: ICISSP, ISBN 978-989-758-282-0, pages 41-51. DOI: 10.5220/0006577600410051


in Bibtex Style

@conference{icissp18,
author={Thomas Gougeon and Patrick Lacharme},
title={How to Break CaptchaStar},
booktitle={Proceedings of the 4th International Conference on Information Systems Security and Privacy - Volume 1: ICISSP,},
year={2018},
pages={41-51},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0006577600410051},
isbn={978-989-758-282-0},
}


in EndNote Style

TY - CONF

JO - Proceedings of the 4th International Conference on Information Systems Security and Privacy - Volume 1: ICISSP,
TI - How to Break CaptchaStar
SN - 978-989-758-282-0
AU - Gougeon T.
AU - Lacharme P.
PY - 2018
SP - 41
EP - 51
DO - 10.5220/0006577600410051