Attacks against process control systems

A cyber‐secure control‐detector architecture for nonlinear processes

“…As intelligent cyber‐attacks are adaptive to the process and control system behavior, we may assume that they are as powerful as having access to the measurement feedback signals (sensor attack), the control command signals (actuator attack), or auxiliary information such as the threshold and bias parameters in detection methods such as CUSUM . Being process and controller behavior aware, the attacks will therefore have information on the stability region of the process under two‐tier control, as well as existing alarm triggers on the ideal operating window imposed on the input and output variables.…”

“…Intelligent cyber‐attacks are designed such that the controller is able to compute feasible control actions (i.e., the falsified state is not outside the closed‐loop stability region Ω ρ ), but have large enough magnitude of variations such that the control system will not be able to drive the process to its operating steady state. The four most important types of such attacks are considered below.…”

“…There are many advantages to using a databased approach to develop the cyber‐attack detector . First, with attacks having possible access to information on process behavior (stability region and variable operating window), physical‐model‐based detection methods where the statistics threshold and false alarm bias are selected based on process operation are rendered ineffective . Second, during real‐life operation, plant model structure and parameters may be subject to modifications due to a changing operating environment.…”

Design-time Quantification of Integrity in Cyber-physical Systems

“…Traditional IT security mechanisms such as authentication and message integrity are insufficient for CPS security. However, as stated in [13], the major distinction of control systems with respect to other IT systems is the interaction with the physical world. In [25], the authors state that CPSs security is specifically concerned with attacks that cause physical impact; since IT security mechanisms do not usually account for the physical part of the system, they are thus ineffective against attacks that either target or exploit the physical components of CPSs.…”

“…Integrity attacks include stealthy attacks [19], message replay [36], covert attacks [50], and false-data injection [37], among others. Due to their focus on fault-detection techniques, many results based on control theory aim to protect CPSs from integrity attacks by relying on monitoring the physics of the system to detect anomalies (see, e.g., [5,13,35,38,44,52]).…”