Consider the following data 
<<script (not real script)>script (dirty nasty stuff)>

[download]
Trust me, this is not a bogeyman. merlyn is saying that it is a mistake to think in terms of just trying to remove known dangerous constructs because it is. That way lies madness.

Decide what you will allow, and explicitly escape everything that does not fit a known and specified safe pattern.

In reply to Re (tilly) 2: Opinions needed on CGI security by tilly
in thread Opinions needed on CGI security by Gryphaan

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