reCAPTCHA bypass via HTTP Parameter Pollution

In Summary :

reCAPTCHA is a Google service that allows web application developers to add a CAPTCHA to their site with minimal effort. reCAPTCHA is a complex beast with a lot of use cases: sometimes it will trust you based on your existing cookies, sometimes it will require you to solve multiple challenges. The following introduction is for the use case where the vulnerability was found. [...]

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https://ift.tt/2sizVjX