title: Secure Python Markdown Library
body: <p>I'd like to enable users to leave rich text comments, possibly using markdown. I've installed the libraries used on Reddit, but am concerned about the javascript injection attack which occurred last year, especially since I'm still not clear on the details of how the attack was done. Should I still be concerned about comment security? Is there a test string I can put through my system to check for the same flaws that took down reddit?</p>