Just for starters, ??{ . . . } can be used to execute code. That would be bad. There's also nothing stopping future versions of Perl to add some other way to execute code or do other nasty things if you let the search string go through. So even if you're safe now, you might not be safe when you upgrade Perl a few years from now.

You absolutely need to have a deny-by-default policy. Run the string through something like this before searching:

if( $search !~ /\A ([A-Za-z0-9 ]+) \z/x ) {
    print "Error, can't run search\n";
}

[download]

You can add in as many characters as you need, but I suspect most searches don't need anything more than ASCII upper- and lower-case, numbers, and a space.

"There is no shame in being self-taught, only in not trying to learn in the first place." -- Atrus, Myst: The Book of D'ni.

In reply to Re: Site Search perlscript and security by hardburn
in thread Site Search perlscript and security by steelrose

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