Research on Memory Attacks and Defenses for Programmable Logic Controllers

Programmable logic controllers (PLCs) are the core of industrial control systems (ICS), which play an essential role in critical infrastructure. In recent years, significant real-world attacks against PLCs have emerged, causing devastating consequences to critical infrastructure. In this paper, we first introduce the architecture and memory system of PLC. We then systematically analyze the existing PLC memory attack methods and classify them into five types according to different attack vectors. Subsequently, we present three types of mainstream PLC memory attack detection methods and compare the detection ability against our proposed memory attacks. Finally, we discuss the challenges of existing PLC memory attack detection.