Thanks. I've read your course before (very helpful, BTW), but I must have stopped remembering the poison null byte when I saw this line, "However, the real fix is to avoid letting user data near the shell."

This script will never, ever, let anyone pass a shell command (AFAIK; see next question). If this is the case, can I safely ignore said null byte, or should I strip it out just for fun? Also, see my reply above (directly below, the way this threading works) to tadman - I'm running with Taint on, and explicitly untainting every parameter I accept with a regex of "allowed" characters.

If I do decide to pass shell commands, is your 1-liner $data =~ s/\x00//g; sufficient to guard against this problem?
--
man with no legs, inc.

In reply to Re: (Ovid) Re(4): CGI OO 'param' vs. hash by legLess
in thread CGI OO 'param' vs. hash by legLess

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