That ("unlink...") will not work from inside the /regexp/ which is the only place the $userinput will appear inside eval{}. I did test it, but I'm no expert on exploitation.

Running in taint mode, the first version: 
eval($s);

[download]
will throw an error, whereas the second does not (for what that is worth). The first form is the only one I can actually get code to execute in (via the input). Perhaps I am being a little paranoid suddenly.

In reply to Re^2: eval() and security by halfcountplus
in thread eval() and security by halfcountplus

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