Cyber Resiliency of Aircraft Systems – A Literature Review

Aircraft have an important role in the overall defense of almost every country. However, military aircraft are not only susceptible to traditional kinetic weapons but also to constantly developing cyber weaponry. There has been global growth in the number of cyber threats in recent years, and the field of military aviation is not outside the growing threat. The war in Ukraine and recent military aircraft procurements in Europe make the topic very timely. A highly skilled and resourced adversary is able to conduct complex long-term attacks that penetrate even well-protected systems, such as military aircraft systems. Even air-gap does not protect aircraft from cyber threats as modern aircraft have complex and networked avionics and support systems. The study aims to find the current trends of cyber security research related to aircraft systems. The included topics are, for example, cyber resiliency and cyber protection in the system life cycle. The study concentrates particularly on forming an overall view of the most vulnerable military aircraft systems. The study presents a non-systematic literature review based on public data sources, such as research reports, articles, etc. A set of nine relevant sources was chosen for detailed qualitative analysis. Because of the lack of detailed military sources, applicable study materials related to commercial passenger aircraft were included. The results suggest that the most vulnerable aircraft systems from the viewpoint of cyber security are those that are exposed to threats via communication and satellite systems. Other vulnerable systems are sensors and avionics systems that transfer, or process critical data related to the functions of the aircraft. In addition, the study found that it is difficult to protect aircraft systems from cyber threats because of their complexity, maintenance operations, and supply chains, which also increase the size of the attack vector. To tackle the issue, it is important to follow the development of regulations and policies related to cyber security in aviation and to study the methods of managing the threat in a holistic and cost-effective manner.