With the development of in-vehicle network technologies, Automotive Ethernet is being applied to modern vehicles. Scalable service-Oriented MiddlewarE over IP (SOME/IP) is an automotive middleware solution that is used for communications of the infotainment domain as well as that of other domains in the vehicle. However, since SOME/IP lacks security, it is vulnerable to a variety of network-based attacks. In this paper, we introduce a new type of intrusion detection system (IDS) leveraging on SOME/IP packet's header information and packet reception time to deal with SOME/IP related network attacks.