SQL injection vulnerability in index.php, possibly during a showtopic operation, in Invision Power Board (IPB) 2.1.5 allows remote attackers to execute arbitrary SQL commands via the st parameter.
https://exchange.xforce.ibmcloud.com/vulnerabilities/25254
http://www.securityfocus.com/archive/1/430357/100/0/threaded
http://www.securityfocus.com/archive/1/426875/100/0/threaded