Decaptcha breaking 75% of ebay audio captchas

Elie Bursztein; Steven Bethard

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Decaptcha breaking 75% of ebay audio captchas

Available Media
Available Media	Publication (PDF) Slides (PDF)
Conference	3rd USENIX Workshop On Offensive Technologies (WOOT) - 2009
Authors	Elie Bursztein , Steven Bethard
Citation	BibTeX BibTeX `@inproceedings{Bursztein2009Decaptcha, title = {Decaptcha breaking 75% of ebay audio captchas}, author = {Elie Bursztein and Steven Bethard}, booktitle = {3rd USENIX Workshop On Offensive Technologies}, year = {2009}, organization = {Usenix} }`

CAPTCHA tests aim at preventing attackers from performing automatic registration. In this paper we show that our prototype Decaptcha is able to successfully break 75% of eBay audio captchas. We compare its performance with the state of the art, readily available speech recognition system Sphinx and discuss the implications for eBay security.

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