Cross-site scripting (XSS) vulnerability in guestbook.php in Advanced Guestbook 2.4 for phpBB allows remote attackers to inject arbitrary web script or HTML via the entry parameter. NOTE: this issue might be resultant from SQL injection.
https://exchange.xforce.ibmcloud.com/vulnerabilities/27907
http://www.majorsecurity.de/advisory/major_rls25.txt
http://securityreason.com/securityalert/2323
http://secunia.com/advisories/19905
http://archives.neohapsis.com/archives/bugtraq/2006-07/0381.html