Cacti is an open source performance and fault management framework. The `fileurl` parameter is not properly sanitized when saving external links in `links.php` . Morever, the said fileurl is placed in some html code which is passed to the `print` function in `link.php` and `index.php`, finally leading to stored XSS. Users with the privilege to create external links can manipulate the `fileurl` parameter in the http post request while creating external links to perform stored XSS attacks. The vulnerability known as XSS (Cross-Site Scripting) occurs when an application allows untrusted user input to be displayed on a web page without proper validation or escaping. This issue has been addressed in release version 1.2.28. All users are advised to upgrade. There are no known workarounds for this issue.