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We present a black-box attack against an already deployed CAPTCHA that aims to protect a free service delivered using the Internet. This CAPTCHA, referred to as “Math CAPTCHA” or “QRBGS CAPTCHA”, requests the user to solve a mathematical problem in order to prove human. We study significant problems both in its design and its implementation, and how those flaws can be used to completely solve this...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.