Why isn't ValidateRequest="true" enough for XSS prevention?

Posted by Microserf on Stack Overflow See other posts from Stack Overflow or by Microserf
Published on 2010-04-01T09:19:18Z Indexed on 2010/04/01 9:23 UTC
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Filed under:

ASP.NET

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c#

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.NET

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xss

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cross-site-scripting

In the notes for Step 1 in the "How To: Prevent Cross-Site Scripting in ASP.NET" it is stated that you should "not rely on ASP.NET request validation. Treat it as an extra precautionary measure in addition to your own input validation."

Why isn't it enough?

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