Biblio
The Controller Area Network (CAN) protocol has become the primary choice for in-vehicle communications for passenger cars and commercial vehicles. However, it is possible for malicious adversaries to cause major damage by exploiting flaws in the CAN protocol design or implementation. Researchers have shown that an attacker can remotely inject malicious messages into the CAN network in order to disrupt or alter normal vehicle behavior. Some of these attacks can lead to catastrophic consequences for both the vehicle and the driver. Although there are several defense techniques against CAN based attacks, attack surfaces like physically and remotely controllable Electronic Control Units (ECUs) can be used to launch attacks on protocols running on top of the CAN network, such as the SAE J1939 protocol. Commercial vehicles adhere to the SAE J1939 standards that make use of the CAN protocol for physical communication and that are modeled in a manner similar to that of the ISO/OSI 7 layer protocol stack. We posit that the J1939 standards can be subjected to attacks similar to those that have been launched successfully on the OSI layer protocols. Towards this end, we demonstrate how such attacks can be performed on a test-bed having 3 J1939 speaking ECUs connected via a single high-speed CAN bus. Our main goal is to show that the regular operations performed by the J1939 speaking ECUs can be disrupted by manipulating the packet exchange protocols and specifications made by J1939 data-link layer standards. The list of attacks documented in this paper is not comprehensive but given the homogeneous and ubiquitous usage of J1939 standards in commercial vehicles we believe these attacks, along with newer attacks introduced in the future, can cause widespread damage in the heavy vehicle industry, if not mitigated pro-actively.
AbstractCyber assurance of heavy trucks is a major concern with new designs as well as with supporting legacy systems. Many cyber security experts and analysts are used to working with traditional information technology (IT) networks and are familiar with a set of technologies that may not be directly useful in the commercial vehicle sector. To help connect security researchers to heavy trucks, a remotely accessible testbed has been prototyped for experimentation with security methodologies and techniques to evaluate and improve on existing technologies, as well as developing domain-specific technologies. The testbed relies on embedded Linux-based node controllers that can simulate the sensor inputs to various heavy vehicle electronic control units (ECUs). The node controller also monitors and affects the flow of network information between the ECUs and the vehicle communications backbone. For example, a node controller acts as a clone that generates analog wheel speed sensor data while at the same time monitors or controls the network traffic on the J1939 and J1708 networks. The architecture and functions of the node controllers are detailed. Sample interaction with the testbed is illustrated, along with a discussion of the challenges of running remote experiments. Incorporating high fidelity hardware in the testbed enables security researchers to advance the state of the art in hardening heavy vehicle ECUs against cyber-attacks. How the testbed can be used for security research is presented along with an example of its use in evaluating seed/key exchange strength and in intrusion detection systems (IDSs).