Cross-site scripting (XSS) vulnerability in index.php in Max's Guestbook allows remote attackers to inject arbitrary web script or HTML via the (1) name, (2) email, and (3) message parameters.
https://exchange.xforce.ibmcloud.com/vulnerabilities/74011
https://exchange.xforce.ibmcloud.com/vulnerabilities/47250
http://www.securityfocus.com/bid/52471
http://www.securityfocus.com/bid/32763
http://www.securityfocus.com/archive/1/499099/100/0/threaded
http://www.exploit-db.com/exploits/18595