Multiple cross-site scripting (XSS) vulnerabilities in the DMSGuestbook 1.7.0 plugin for WordPress allow remote attackers to inject arbitrary web script or HTML via the (1) file parameter to wp-admin/admin.php, or the (2) messagefield parameter in the guestbook page, and the (3) title parameter in the messagearea.
https://www.exploit-db.com/exploits/5035
http://www.securityfocus.com/archive/1/487437/100/0/threaded