Greetings Brothers,

I'm writing a simple text search CGI script. The user types in a search term, and I perl grep through a datastructure of the text and return data.

At the moment I untaint the user input by allowing only "word like" characters and such. However, I'd like to allow the users to use regular expressions in their searches. However, I am not enough of a regex master to know what to allow/disallow. I've been told that you can execute code in a regex, so that makes me nervous about accepting any regex.

Is there a tool or any hints as to how I could safely allow this? Any input would be greatly appreciated!

rasto

In reply to untainting regex input by rastoboy

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