A Survey on Sensor False Data Injection Attacks and Countermeasures in Cyber-Physical and Embedded Systems.

Cyber-physical system (CPS) and embedded system (ES) has been growing rapidly, embracing safety-critical systems such as automobiles and airplanes. While such systems are traditionally operated by human, recent technology enables autonomous operation, even making critical control decisions by itself. Since decision-making process highly depends on sensor data, it is crucial for safety that outputs from sensors should remain trustworthy at all times. Sensor false data injection (SFDI) attacks target sensors of CPS and ES, to affect their outputs, ultimately to perturb behavior of the entire system. In a sensor, raw signal is processed at multiple stages to return the measurement. We group them into three layers where signal changes its form. The simple three-layer view can help analyze existing attacks and defenses systematically: where the root cause of an attack is, how an attack is propagating, which layer a defense can protect. The goals of the survey are to (1) understand the literature of SFDI attacks and defenses clearly, (2) identify current challenges and potential approaches to make sensors secure.