code.php in PC4Arb Pc4 Uploader 9.0 and earlier makes it easier for remote attackers to conduct SQL injection attacks via crafted keyword sequences that are removed from a filter in the id parameter in a banner action, as demonstrated via the "UNIunionON" string, which is collapsed into "UNION" by the filter_sql function.
https://www.exploit-db.com/exploits/8709
https://exchange.xforce.ibmcloud.com/vulnerabilities/50586
http://www.vupen.com/english/advisories/2009/1364