Communications play a fundamental role in the economic and social well-being of the citizens and on operations of most of the Critical Infrastructures (CIs). 5G networks and future communications technologies radically transform the way we communicate, by introducing a vast array of new connections, capabilities and services in a multiplicity of sectors. In this scope, network function virtualization and end-to-end network slicing are two promising technologies empowering 5G networks for efficient and dynamic network/service deployment and management. Resilience of critical infrastructure systems and especially in telecommunication networks can be considered as “key factor” that can reduce vulnerability, minimize the consequences of threats as well as their cascade effects, accelerate mitigation and facilitate re-adaptation to a disruptive event. In this context, comprehensive knowledge of the complete surrounding environment and of the most important factors that affect and/or determine resilience, can evolve at a fundamental aspect concerning the case resilience of critical telecommunication. Based on this idea, the RESISTO project provides a holistic situation awareness for telecommunication infrastructures and simultaneously enhances resilience, while acting as an on top safety net boosting the faster and more reliable management enabling the digital transformation of our society and a variety of business processes. In this paper we specifically discuss the impact of the RESISTO platform when a security breach occurs in a 5G mobile network.