A flaw was found in jboss-remoting in versions before 5.0.20.SP1-redhat-00001. A malicious attacker could cause threads to hold up forever in the EJB server by writing a sequence of bytes corresponding to the expected messages of a successful EJB client request, but omitting the ACK messages, or just tamper with jboss-remoting code, deleting the lines that send the ACK message from the EJB client code resulting in a denial of service. The highest threat from this vulnerability is to system availability.