Webupon

Web applications show captchas when a user wants to sign up for a new account, or when a user wants to post a comment, just like the security code you have to type when you post a comment on a Triond article.

The goal of these captchas is to block bots from spamming and abusing websites. Most captchas consist out of (mostly distorted) characters. The user has to type those characters in a box. But there are bots out there that use OCR-technology (Optical Character Recognition) to convert pictures to text, and still bypass captcha security. That’s why Google invented this new captcha type.

Other companies have attempted to design stronger captchas too, by displaying pictures of cats and dogs, asking the user to click on a cat or a dog. Sophisticated bots can still bypass these tests, nevertheless.

Google’s new type of captcha asks users to rotate pictures till they appear upright. This simple but effective tasks requires people to analyze the picture for a few seconds, which something that a bot can’t do.

“This new captcha technique does not require any text input by the user, and is nicer for users than a regular text-based captchas.”

The challenge in creating captchas, is to find a good balance between captchas that are too easy, and captchas that are way too confusing for legit humans. It’s very hard to determine the upper side or lower side from some pictures, while other pictures (mostly landscape pictures) are easy to bypass for bots.

Some bots can even identify that the lower side of a landscape picture is blue. That means that the blue is the colour of the sky. The bot will then rotate the picture horizontally. Same goes for a picture with a green upper side. That would be a rotated picture of a grass field. The bot will then rotate the picture horizontally as well.

Google has now created this new captcha to fool the bots once again. They have also implemented a kind of interactive ‘voting system’. Users do vote indirectly by filling in the captchas: if many users fail to solve one certain captcha, the captcha will not be shown anymore. Successful captchas are being saved in a library to use again in the future.

This is a nice new technique developed by Google. We all know the story though: first, a new security technique is being released. Afterwards, the bots get smarter and are able to circumvent the new security technique. We’ll see how long it takes for the bots to circumvent this new technique. Below, you can see a sample of Google’s new type of captchas.