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This Machine Kills Captchas (vice.com)

Posted by msmash on from the catch-me-if-you-can dept.

New submitter dmoberhaus writes: It is with a heavy heart that I must tell you that an artificial intelligence has finally cracked a widely used tool that was literally made to differentiate humans from robots: the CAPTCHA. CAPTCHAs are the annoying puzzles that might ask you to rewrite a piece of distorted text or click on all the automobiles in a photograph to log on to sites like PayPal. According to research published today in Science, a new type of AI was able to solve certain types of CAPTCHA with up to 66.6 percent accuracy. To put this in perspective, humans can solve the same type of CAPTCHA with about 87 percent accuracy due to multiple interpretations of some examples and a CAPTCHA is considered broken if a bot can pass it 1 percent of the time.

4 of 101 comments (clear)

  1. Didn't google do away with those? by freeze128 · · Score: 4, Informative

    I thought google implemented a captcha that looks at your browsing and usage history to determine if you're a bot or not. There isn't any picture-picking or wobbly word typing involved.

    1. Re:Didn't google do away with those? by Anonymous Coward · · Score: 3, Informative

      In theory. In practice it click on several dozen squares to find roadsigns or cars, and you have to click reaaaaallly slowly or it doesn't work. Google's CAPTCHA is the single most horrible one ever conceived.

  2. Re:What? by Anonymous Coward · · Score: 2, Informative

    Nowadays a lot of captchas are just a 9x9 grid of images where you have to choose which ones match. 1/2^9 is 1/512, but realistically you only click 2 or 3 so 1/(9 choose 2 + 9 choose 3) = 1/120. Not much different from 1%.

  3. Re:What? by Dutch+Gun · · Score: 5, Informative

    After reading the article (a dangerous pastime, I know), I think the summary is really focusing on the wrong aspects of this new algorithm. The innovation of this approach is NOT in its accuracy. Other algorithms have approached a 90% success rate, but required significantly larger data sets to train and were more brittle. For instance, minor adjustments in things like character spacing could throw it off, requiring re-training.

    The critical part of this approach is its greater flexibility in solving different types of CAPTCHAs, and the reduced amount of training required in order to get it up to a reasonable level of accuracy.

    --
    Irony: Agile development has too much intertia to be abandoned now.