Just to add to all the posters above, who focus more on
untainting the data, perldoc perlsec gives this example
to beforehand check if the data is actually tainted: 
sub is_tainted {
 return ! eval {
  join('',@_), kill 0;
  1;
 };
}

[download]

GreetZ!,

print "profeth still\n" if /bird|devil/;

In reply to Re: Homegrown Pseudo-Tainting by ChOas
in thread Homegrown Pseudo-Tainting by oubiwann

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