Engadget RSS Feed http://www.engadget.com Engadget http://www.blogsmithmedia.com/www.engadget.com/media/feedlogo.gif Engadget http://www.engadget.com en-us Copyright 2013 AOL Inc. The contents of this feed are available for non-commercial use only. Blogsmith http://www.blogsmith.com/ <![CDATA[Stanford program cracks text-based CAPTCHAs, shelters the replicants among us]]> http://www.engadget.com/2011/11/02/stanford-program-cracks-text-based-captchas-shelters-the-replic/?utm_medium=feed&utm_source=Feed_Classic&utm_campaign=Engadget http://www.engadget.com/2011/11/02/stanford-program-cracks-text-based-captchas-shelters-the-replic/ http://www.engadget.com/2011/11/02/stanford-program-cracks-text-based-captchas-shelters-the-replic/?utm_source=Feed_Classic&utm_medium=feed&utm_campaign=Engadget#comments CAPTCHAs. In the absence of a Voigt-Kampff apparatus, they're what separate the humans from the only-posing-to-be-human. And now three Stanford researchers have further blurred that line with Decaptcha, a program that uses image processing, segmentation and a spell-checker to defeat text-based CAPTCHAs. Elie Bursztien, Matthieu Martin and John Mitchell pitted Decaptcha against a number of sites: it passed 66% of the challenges on Visa's Authorize.net and 70% at Blizzard Entertainment. At the high end, the program beat 93% of MegaUpload's tests; at other end, it only bested 2% of those from Skyrock. Of the 15 sites tried, only two completely repelled Decaptcha's onslaught -- Google and reCaptcha. So what did the researchers learn from this? Randomization makes for better security; random lengths and character sizes tended to thwart Decaptcha, as did waving text. How long that will remain true is anyone's guess, as presumably SkyNet is working on a CAPTCHA-killer of its own.

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]]> captchacaptchasDecaptchadeckardElie BursztienElieBursztienGoogleJohn MitchellJohnMitchellMatthieu MartinMatthieuMartinMegaUploadPhillip K. DickPhillipK.DickreCaptchareplicantskynetSkyrockStanfordVoigt-Kampff apparatusVoigt-kampffApparatus Wed, 02 Nov 2011 20:40:00 -0400 21|20096851