CANvas: Fast and Inexpensive Automotive Network Mapping

"Modern vehicles contain tens of Electronic Control Units (ECUs), several of which communicate over the Controller Area Network (CAN) protocol. As such, in-vehicle networks have become a prime target for automotive network attacks. To understand the security of these networks, we argue that we need tools analogous to network mappers for traditional networks that provide an in-depth understanding of a network’s structure. To this end, our goal is to develop an automotive network mapping tool that assists in identifying a vehicle’s ECUs and their communication with each other. [...] CANvas generates network maps in under an hour that identify a previously unknown ECU in a 2009 Toyota Prius and identify lenient message filters in a 2017 Ford Focus."

https://www.usenix.org/system/files/sec19-kulandaivel.pdf