rmserver in RealNetworks Helix Server and Helix Mobile Server before 13.0.0 allows remote attackers to cause a denial of service (daemon exit) via multiple RTSP SET_PARAMETER requests with empty DataConvertBuffer headers.
http://www.vupen.com/english/advisories/2009/1947
http://www.securityfocus.com/bid/35731
http://www.securityfocus.com/archive/1/505083/100/0/threaded
http://www.exploit-db.com/exploits/9198
http://docs.real.com/docs/security/SecurityUpdate071409HS.pdf