This starts it all: 
print '<a href="#" onClick="var xmlHttp = null;
    xmlHttp = new XMLHttpRequest();
    xmlHttp.open( &quot;GET&quot;,
      &quot;/cgi-bin/bid.js?aid='.(
        $rBid->{cgi}->param('aid')||-1
      ).'&quot; , false );
    xmlHttp.send( null );
    eval(xmlHttp.responseText);
    return false;">[Bid]</a>
';

[download]

In the above I'm scared that content from the client is being passed without first being quoted. I should escapeHTML this at the vary least, but this is not enough and whatever function I used needs to be secure enough for the job... Ideally I'd only use something provided by the specific make, model, and version of the processor. Understanding this is a remote web browser I'm willing to make certain concessions... Like using escapeHTML or URL escape functions provided by notable CPAN modules.

This is where the problem is: 
print $rBid->{session}->header(-type=>'text/javascript');
my $sth = $rBid->{dbh}->prepare(
'INSERT INTO bid VALUES (?, (SELECT bidder_username
  FROM session WHERE id=?));') or die $rBid->{dbh}->errstr;
$sth->execute($rBid->{cgi}->param('aid'),
  $rBid->{session}->id()||'undef') or
  print 'alert("Error: '.
    $rBid->{cgi}->escapeHTML($sth->errstr).'");'."\n";

print 'alert("Bid(s) Placed: '.
  $rBid->{cgi}->escapeHTML($sth->rows).'");'."\n";

[download]
The escapeHTML above is interpreted by the JS and not the HTML processor, as there is no HTML processor. I could switch to using alert('... but then I'd need to escape '.

In reply to Re^2: Perl, JavaScript and quoting/escaping by Anonymous Monk
in thread Perl, JavaScript and quoting/escaping by isync

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