Blackhat SEO – Esrun

Although the captcha shown in the image to the left may appear like any other captcha, DynaDot are actually using a HTML table based captcha to defend against automated WHOIS lookups.

This works by splitting each character into multiple rows. Each row is it’s own table, with each cell (TD) set to a specific height, width and background color.

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Continue reading DynaDot HTML table captcha…

Someone on the WickedFire forums came across an interesting problem. He needed to automate the submission of data to a website which used a relatively simple looking captcha.

Usually for a simple looking captcha like this, you’d just feed the image straight through gocr which would output plain text. If the captcha is more complicated then you have to write your own OCR code.

This captcha however, is deceiving. It’s not actually an image. It’s a mishmash of HTML and CSS!

Continue reading HTML based Captcha…