On a lark I took a quick trip out to CPAN - here's my suggestion written down as probably-useable code (meaning I didn't test it). It installs a filter on the STDOUT filehandle before script execution so no tainted data is allowed to print. Obviously if you start handling user-input prior to this INIT block then that isn't covered but you shouldn't do that anyway.

This can be enhanced by using an exception 

 package Filter::Handle::Tainted;
 # Put this code into the package just to have a reasonable
 # place to live.
 
 use Filter::Handle qw(subs);
 use Taint qw(tainted);
 use Exception::Class qw(Filter::Handle::Tainted::TaintException);
 INIT {
     Filter
         \ *STDOUT,
         sub {
             for (@_) {
                 next unless tainted( $_ );

                 # Tainted data was about to be printed to
                 # the handle. Throw an exception instead.
                 Filter::Handle::Tainted::TaintException
                   -> throw( error =>
                             "Tainted data may not be written to this 
+io handle." );
             }
         };
 }

[download]

Fun Fun Fun in the Fluffy Chair

In reply to Re: Using taint mode to prevent XSS holes by diotalevi
in thread Using taint mode to prevent XSS holes by IlyaM

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.