Quantum Cyber Threats and Their Impact on the Security of Critical Information Infrastructure

The use of quantum technologies in the modern world poses significant challenges to the security of critical information infrastructure, which underpins key sectors such as healthcare, energy, transportation, and communications. Cryptographic algorithms like RSA and ECC, long considered reliable, have lost their resilience in the face of quantum computing capabilities, making the search for modern solutions to ensure data protection a top priority. The main risks posed by quantum computers include the potential compromise of encryption algorithms, disruption of data integrity, and destabilization of critical system operations. The methodological foundation of this study is based on the analysis of 318 sources from international databases such as Scopus and Web of Science. From this body of literature, 24 publications most relevant to the topic were selected. A comparative method was employed to analyze classical and quantum threats. The aim of the study is to examine the impact of quantum attacks on the security of critical information infrastructure (CII) at the current level and propose pathways for transitioning to quantum-resilient solutions. The results emphasize the necessity of implementing innovative cryptographic approaches, such as lattice-based and code-based algorithms, as well as combined (hybrid) technologies. Successful protection of the infrastructure requires a systematic approach, including a comprehensive audit of existing systems, training of specialists, and the removal of technical and regulatory barriers. The developed step-by-step plan minimizes risks and establishes a foundation for the secure implementation of new standards.