Unrestricted file upload vulnerability in admin.php in PBBoard 2.1.4 allows remote administrators to execute arbitrary PHP code by uploading a file with an executable extension, then accessing it via a direct request to the file in the addons directory. NOTE: this vulnerability can be leveraged by remote attackers using CVE-2012-1216.
https://www.htbridge.com/advisory/HTB23101
https://exchange.xforce.ibmcloud.com/vulnerabilities/77508
http://www.pbboard.com/forums/t10352.html