Completely ignoring the problems (such as the shebang line and the $cf,$ct issue) since those have been answered by other posts...

Why use CGI, then make life hard on yourself?

#!/usr/bin/perl

use CGI;

my $q = new CGI;
my $cf = $q->param('cf'); # Needs to be untainted

print $q->header,
  $q->start_html,
  $q->h2("$cf,$ct");
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No reason to code the HTML up yourself if you're already incorporating CGI...