Software cracks CAPTCHAs -

A technology start-up has written software to crack CAPTCHAs.

CAPTCHAs are supposed to prove that you are human and have good eyesight, but if either can be proved by software the security system is basically doomed.

According to Mashable, Vicarious co-founder Scott Phoenix said that his company developed the algorithm not for any nefarious purpose and not even to sell, said.

He wanted to create a machine which works like the human brain.

The company has not submitted a paper describing its methodology to an academic journal, which makes it difficult for outside experts to evaluate the claim.

Vicarious offers a demonstration of its technology at vicarious.com, showing its algorithm breaking CAPTCHAs from Google and eBay's PayPal.

CAPTCHAs can be broken by paying people in Bangladesh to do it manually. For 50 cents an hour, you can get someone to break seven per minute, he reckons.

Vicarious said its algorithm achieves success rates of 90 to 97 percent, depending on the difficulty of the CAPTCHA; a CAPTCHA scheme is considered broken if a machine can break just one  percent of the ones it generates.

Google's reCAPTCHA uses words from old books and other publications that have been optically scanned but are difficult to digitise because they are so degraded.

The feat required relatively tiny amounts of data and computing power, Vicarious said, instead using algorithms that mimic the perceptual and cognitive abilities of the human brain.