El, Ahmad Salah and Yan, Jeff and Marshall, Lindsay (2010) The robustness of a new CAPTCHA. In: Proceedings of the 3rd European Workshop on System Security, EUROSEC'10. ACM, FRA, pp. 36-41. ISBN 9781450300599
Full text not available from this repository.Abstract
CAPTCHA is a standard security technology that presents tests to tell computers and humans apart. In this paper, we examine the security of a new CAPTCHA that was deployed until very recently by Megaupload, a leading online storage and delivery website. The security of this scheme relies on a novel segmentation resistance mechanism. However, we show that this CAPTCHA can be segmented using a simple but new automated attack with a success rate of 78%. It takes about 120 ms on average to segment each challenge on a standard desktop computer.