I'm a bit confused by a taint warning I'm getting. After several hours simplifying my problem, I'm left with this code: 
#!/usr/bin/perl -wT
#
use strict;

  my $foo = {
        'clean'         => 'filename.txt',
        'dirty'         => scalar(<>),
  };
  open(F,"+>{$foo->{clean}}");
  close(F);

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which returns this: Insecure dependency in open while running with -T switch at ./taint_puzzle.pl line 9, &lt;&gt; line 1.

Now, to me this seems cut and dry - $foo->{dirty} is tainted, but $foo->{clean} smells like daisies. If the two variables are kept in seperate scalars, there's no problem - $foo->{clean} seems to be becoming tainted merely by association.

Why is it so?

- Boldra

In reply to tainted entangled hashrefs by Boldra

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