Stack-based buffer overflow in JDBC Applet Server in IBM DB2 8.1 allows remote attackers to execute arbitrary by connecting and sending a long username, then disconnecting gracefully and reconnecting and sending a short username and an unexpected db2java.zip version, which causes a null terminator to be removed and leads to the overflow.
https://exchange.xforce.ibmcloud.com/vulnerabilities/17613
http://www.securityfocus.com/bid/11401
http://www.nextgenss.com/advisories/db205012005D.txt
http://www-1.ibm.com/support/docview.wss?uid=swg1IY61492