IBM Informix Dynamic Server (IDS) before 9.40.xC7 and 10.00 before 10.00.xC3 does not use database creation permissions, which allows remote authenticated users to create arbitrary databases.
https://exchange.xforce.ibmcloud.com/vulnerabilities/28148
http://www.vupen.com/english/advisories/2006/3077
http://www.securityfocus.com/bid/19264
http://www.securityfocus.com/archive/1/443192/100/0/threaded
http://www.securityfocus.com/archive/1/443133/100/0/threaded
http://www.databasesecurity.com/informix/DatabaseHackersHandbook-AttackingInformix.pdf