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MIME Sniffing in IE

Today I was going through an interesting article. It was about executing XSS through uploading an image hiding script in it. This is not new and has been out there for quite some time. But IE handles it less responsibly whereas FF and Opera simply prints the URL and broken image respectively instead of executing the script.
For example, in Google Page Creator , there is an upload section which can be used to upload image file or say files with only .jpg,.bmp,.png extensions. But hiding a script inside an image file with valid extension (.jpg) gets uploaded successfully and gets executed....but only in IE not otherwise. This might me an expected behavior of Google pages but the point is the way IE handles it.
Few months ago before publishing of this article, I and my colleague Chintan had found it and discussed about it. That gave a strike to my mind today while reading the article on Owasp, that this we are already familiar with.
Anyways the article could be read on http://www.rorsecurity.info/journal/2009/2/11/mime-sniffing-in-ie-enables-xss-attacks.html

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