A Parsing Mode based Method for Malformed SIP Messages Testing for IMS Network

IMS(IP Multimedia Subsystem) network uses SIP (Session Initiation Protocol) as its core control protocol. The defensive ability of the malformed SIP message is particularly important for IMS network security. In this paper, we propose a malformed SIP generation method based on SIP parsing mode and the associated attack testing method. Based on SIP parsing mode of functional entities in IMS, we generate effective malformed SIP messages, which then be used to perform attacking test to IMS functional entities by establishing different session models, so as to evaluate the defensive ability of these entities and provide recommendations for improving the security of the IMS network. We generated a set of malformed SIP messages through this method and apply them to the attacking test of the well-known IMS testbed OpenIMSCore under different session models. The testing finds new vulnerabilities in OpenIMSCore, which shows that our method of malformed SIP messages generation is effective.