ww posted an article that comes to similar conclusions to yours. I'm definitely more inclined toward a whitelist than a blacklist, but I'd much prefer a hard-coded environment for my child process. The original intent of my query was really intended to find out why a scorched earth approach might be problematic. In the kind of code I end up running in these types of situations, there's no reason to not take the draconian approach (PDF generation, numerics, ...). I also try to avoid single-argument system and exec, but that's mostly because I don't trust my escaping talents.

In any case, I'll be using your regex for any values I have to pass through, and I appreciate your thoughts on the matter.

#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.

In reply to Re^4: Taint and Shellshock by kennethk
in thread Taint and Shellshock by kennethk

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