Setting $allow_html to 0 will *attempt* to remove HTML. It will fail if the person supplies a < without a matching >. Fixing it would be convoluted. It's easier to just escape < and >:

if ($allow_html != 1) {
   $value =~ s/</&lt;/g;
   $value =~ s/>/&gt;/g;
}

[download]

Better yet, have a look at secure versions of Matt's scripts.

In reply to Re: Emergency! Our guestbook is getting trashed by HTML! by ikegami
in thread Emergency! Our guestbook is getting trashed by HTML! by JCHallgren

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


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