Buffer overflow in rn5auth.dll in RealNetworks Helix Server and Helix Mobile Server 14.x before 14.3.x allows remote attackers to execute arbitrary code via crafted authentication credentials.
http://www.securitytracker.com/id?1026898
http://www.securityfocus.com/bid/52929
http://helixproducts.real.com/docs/security/SecurityUpdate04022012HS.pdf