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Making CAPTCHAs Even Harder With 3-D Models

Posted by timothy on from the now-what-is-the-man-doing-with-the-rabbit dept.

Michael G. Kaplan writes "CAPTCHA (Completely Automated Public Turing Test to Tell Computers and Humans Apart) are commonly used to prevent computers from filling out web forms. Computer vision experts have been able to design programs to foil CAPTCHA with a high degree of success. I have designed a CAPTCHA that is based on the identification of attributes contained in an image generated by the grouping of easily recognized 3-D objects. I call this the Virtual Photographic CAPTCHA and it is likely to remain invulnerable to automated attack for many years to come. A novel anti-spam system necessitated its development."

4 of 326 comments (clear)

  1. Implementing CAPTCHAs with PHP by shiflett · · Score: 5, Informative

    PHP developers might find this article useful:

    http://phpsec.org/articles/2005/text-captcha.html

  2. I don't like it already by A+beautiful+mind · · Score: 4, Informative

    Check the last sentence on his page.

    "Patents pending."

    Tyvm, but no.

    --
    It takes a man to suffer ignorance and smile
    Be yourself no matter what they say
  3. *blows whistle* Five-minute major... by kapella · · Score: 4, Informative

    ...for not understanding core principles of Ethernet.

    Although it's tangential to the topic, you can't "ban by MAC addresses". Not unless you're on the same ethernet segment as the attacker. Try it the next time you've got access to a few machines separated by at least one router. Ping from two different machines to a third on another network and run tcpdump to inspect the MAC addresses on the packets. Let me know how it turns out. (hint: they'll have the MAC address of the router)

  4. Re:Heh... by farnz · · Score: 3, Informative

    Only works if the originator has a globally unique MAC address. Think dial-up modems, point to point links, private systems using administrator defined addresses (UML hosts for example)...

    --
    I appear to have a blog. Odd.