Clickcha - click the biggest/smallest number for CAPTCHA

Re:Clickcha - click the biggest/smallest number for CAPTCHA by iDope on Thursday May 27, 2010 @05:33AM (#1383134)

Hi,

I am the developer of clickcha. Appreciate the input, but you seem to be forgetting that bruteforcing can be avoided by temporarily banning the IP for some time after certain number of incorrect attempts.

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Re:Clickcha - click the biggest/smallest number for CAPTCHA by zebra on Thursday May 27, 2010 @05:44AM (#1383155)

Don't forget that spammers exploit botnets with tens of thousands zombie computers each one with unique IP. 2.8% from 10000 zombies = 280 first try successful breaches.

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Re:Clickcha - click the biggest/smallest number for CAPTCHA by stoney on Thursday May 27, 2010 @06:24AM (#1383200)

You could make it much harder for bots by asking the user to click on two numbers (e.g. highest and lowest). I don't think that would be too much extra work for the user as most of the effort is in scanning through all of the numbers.

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Re:Clickcha - click the biggest/smallest number for CAPTCHA by niklas on Thursday May 27, 2010 @05:44AM (#1383156)

That's why they use botnets for this. Each attempt will be from a fresh ip.

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Re:Clickcha - click the biggest/smallest number for CAPTCHA by timelinex on Thursday May 27, 2010 @05:48AM (#1383167)

Don't give up though, you are on to something. If you can make the permutation higher then yea you can definitely make it big.

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