Daniel Pereira

Continuous-variable quantum key distribution (CV-QKD) provides a theoretical unconditionally secure solution to distribute symmetric keys among users in a communication network. However, the practical devices used to implement these systems are intrinsically imperfect, and, as a result, open the door to eavesdropper attacks. We present a novel implementation of a coherent detector blinding attack, in which the eavesdropper hinders the capability of the receiver to properly estimate the channel parameters, hiding the impact of their intercept-resend attack. Our results show that excess noise in excess of 2.5 SNU can be reliably hidden by the eavesdropper, thus demonstrating the feasibility of the attack.

Quantum Key Distribution (QKD) promises unprecedented security based on the principles of quantum mechanics. However, practical implementations of QKD systems are susceptible to various side-channel and implementation attacks that can compromise their security. We presents a comprehensive overview of the literature on side channels and implementation attacks on QKD systems, a systematic categorization of different attack vectors and proposed counter measures and analysis of their impact on security. Furthermore, we propose a structured approach for developing standardized tests to evaluate the robustness of QKD systems against these vulnerabilities. Our work aims to bridge the gap between theoretical security and practical implementation, providing a roadmap for future certification of QKD products to be deployed within the European Quantum Communication Infrastructure (EuroQCI).