Buffer overflow in IBM Informix Dynamic Server (IDS) before 9.40.TC7 and 10.00 before 10.00.TC3, when running on Windows, allows remote attackers to execute arbitrary code via a long username.
https://exchange.xforce.ibmcloud.com/vulnerabilities/28122
http://www.vupen.com/english/advisories/2006/3077
http://www.securityfocus.com/bid/19264
http://www.securityfocus.com/archive/1/443149/100/0/threaded
http://www.securityfocus.com/archive/1/443133/100/0/threaded
http://www.databasesecurity.com/informix/DatabaseHackersHandbook-AttackingInformix.pdf