Breaking CAPTCHA with automated humans

Re:Breaking CAPTCHA with automated humans by user24 on Monday January 23, 2012 @07:41AM (#3500142)

But the captcha is randomly distorted afresh each time, so each captcha image will never have been seen before. You'll never get an exact hash match unless you're looking at an extremely naive implementation.

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Re:Breaking CAPTCHA with automated humans by TheSeb on Monday January 23, 2012 @07:52AM (#3500168)

Depends on the implementation, just as you suggested. There are actually quite a few sites that use really simple captchas that don't randomly destort letter placements, lines, colors etc.

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Re:Breaking CAPTCHA with automated humans by troyhunt on Monday January 23, 2012 @07:33PM (#3502864)

During my testing, I literally had a saved bitmap on my local machine which I reissued many, many times. Obviously this meant it was an exact match on each submission.

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Re:Breaking CAPTCHA with automated humans by user24 on Tuesday January 24, 2012 @04:08AM (#3504043)

but that's obviously an edge case rather than something you'd optimise for in the system.

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