IBM DB2 7.0 allows a remote attacker to cause a denial of service (crash) via a single byte to (1) db2ccs.exe on port 6790, or (2) db2jds.exe on port 6789.
https://euvd.enisa.europa.eu/vulnerability/EUVD-2001-1124
http://www.securityfocus.com/bid/3010
http://www.securityfocus.com/archive/1/196140