Cross-site scripting (XSS) vulnerability in the addPost function in data/functions.php in Winn GuestBook before 2.4.8d allows remote attackers to inject arbitrary web script or HTML via the name parameter to index.php. NOTE: some of these details are obtained from third party information.
https://exchange.xforce.ibmcloud.com/vulnerabilities/72025
http://www.exploit-db.com/exploits/18290