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Has CAPTCHAS evolved?

Discussion in 'BlackHat Lounge' started by BlackSeng, Dec 3, 2010.

  1. BlackSeng

    BlackSeng Jr. VIP Jr. VIP

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    I first witness this in .edu forums where the CAPTCHA images are actually seperated. Therefore, if you're using Decaptcher services it will upload only 1 image.

    For example, lets say the CAPTCHA image shows BLACKHATWORLD
    But it will only upload "B" letter image (since it's separated) to the decaptcher service.

    What is more worrisome is forums are now slowly adapting this strategy to beat spammers or decaptcher services.

    Damn... is there a way to overcome this?
    I know software uses the decaptcher API code but it won't be able to upload all the images in a row at once to break it.
     
  2. cyrix

    cyrix Junior Member

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    I've studied OCR and captcha solving software and seperating the characters in a word is actually a step backwards for captchas IMO. One of the biggest challenges software faces when trying to decipher a captcha is distinguishing one character from another in a word because services like recaptcha scew the letters together. Seems like this method is removing that road block making it easier for software solutions to crack. It also wouldn't be difficult at all for a script to take all of the individual character images and recompile them into one image that could be uploaded to a service like decaptcha. Would you be able to provide any URL's of sites that are using this new captcha? I haven't seen any yet myself and would like to check it out :)
     
  3. Gr33nHat

    Gr33nHat Jr. VIP Jr. VIP

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    In our service, we've seen some images that are actually windowed screenshots of the captchas images. So if the whole captcha image is actually 5 images right next to each other, you can screenshot it and just send it over.

    Another way is just to paste the images together in one single image, there are many graphical libraries out there that can do this. You may get a freelancer to make these changes for you for under $200.

    Best Regards,