AI systems are today present in almost every aspect of our lives. This especially considers security of the various types of cyber physical systems (CPS), from the large scale systems like smart grid, smart water distribution, industrial control systems, to the small wearable devices used in healthcare or entertainment. The Cyber Security and Defence research group of JOANNEUM RESEARCH investigated in detail the application of AI systems for targeted cyber-attacks detection, both in network and CPS environment, during the course of the BMK funded project SecFit. Insightful findings indicate that there is still a lot of space for improvement and new applications of AI systems within similar environments, focusing on two main aspects – AI based security and security of AI systems.