Multiple directory traversal vulnerabilities in GL-SH Deaf Forum 6.4.4 and earlier allow remote attackers to include and execute arbitrary local files via a .. (dot dot) in the (1) FORUM_LANGUAGE parameter to functions.php or the (2) style parameter to bottom.php.
https://www.exploit-db.com/exploits/4124
https://exchange.xforce.ibmcloud.com/vulnerabilities/35160