Researchers Crack Google's Audio Captcha

Researchers have managed to crack Google's audio captcha with an average of 85 percent accuracy, allowing bots to automatically create accounts on websites and place spam messages. To distinguish robots from people, captcha's often need to solve puzzles and distorted texts. The captcha of Google also allows users to resolve an audio captcha.

The audio captcha consists of multiple digits read in different speeds, accents and pitches with background noise. Researchers at the University of Maryland devised an attack targeting Google's audio captcha. To crack the audio captcha, the researchers developed " unCaptcha ", software that downloads the captcha audio file and then splits the parts with voice.

The split audio fragment of each digit is then sent to six free online audio transcription services, including Google's. Based on the different results, which figure was read in the audio clip. The results are then entered 'organic' by the software in the captcha window. On average, the software knows how to solve the captcha with 85 percent accuracy. After the researchers published their research ( pdf ), Google has taken various measures that limit the effectiveness of unCaptcha.

Google - Captcha Fighter Against Robots

Google has a new captcha developed to distinguish people on websites of robots, whereby it is no longer necessary to solve a puzzle first. CAPTCHAs are used inter alia for the automatic creation of accounts and post spam on websites counter.

To often distinguishable robots people must puzzles and distorted texts are resolved. Google uses recaptcha example, where there are words from books must be retyped. Our own research shows that the search giant artificial intelligence with an accuracy of 99.8% can solve the puzzles. According to Google would therefore be much easier to apply directly to users whether they are human or robot. This allows users to quickly register or use of a service, which also eliminates the annoyance of solving the captcha.

API

A new API (Application Programming Interface) makes this captcha experience now possible. On websites that use the API receives a large number of users the ability to attach a single click that they are not a robot. Although this sounds simple, the underlying technology is complex, according to the search giant. Last year was a special backend developed that performs a risk if users want to solve a captcha.

On the basis of the way in which the user handles were examined with the captcha or the user was a human. The new API is a development of this, which is looked at many factors which indicate that it is a human being. Where does the risk of insufficient evidence to make this decision will appear captcha again. In addition, the API also makes it possible to test other types of captcha's. The new API would now be used on various websites, including Snapchat, WordPress and Humble Bundle.