Cybersecurity is without doubt becoming a societal challenge. It even starts to affect sectors that were not considered to be at risk in the past because of their relative isolation. One of these sectors is aviation in general, and specifically air traffic management. Nowadays, the cyber security is one of the essential issues of current Air Traffic Systems. Compliance with the basic principles of cyber security is mandated by European Union law as well as the national law. Therefore, EUROCONTROL as the provider of several tools or services (ARTAS, EAD, SDDS, etc.), is regularly conducting various activities, such as the cyber-security assessments, penetration testing, supply chain risk assessment, in order to maintain and improve persistence of the products against the cyber-attacks.