your $file_out is still tainted. You need to re-assign to $file_out a sub-pattern match:

from perlsec, The only way to bypass the tainting mechanism is by referencing subpatterns from a regular expression match. Perl presumes that if you reference a substring using $1, $2, etc., that you knew what you were doing when you wrote the pattern.

so you need to do something like this (modified from perlsec) 

    if ($file_out =~ /^([-\@\w.]+)$/) {
          $file_out = $1;                     # $data now untainted
      } else {
          die "Bad data in $file_out";        # log this somewhere
      }

[download]

-derby

In reply to Re: Taint problem opening file to write by derby
in thread Taint problem opening file to write by fireartist

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