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Vulnerabilities in Quantum Key Distribution Protocols



David R. Kuhn


Recently proposed quantum key distribution protocols are shown to be vulnerable to a classic man-in-the-middle attack using entangled pairs created by Eve. The attack could be applied to any protocol that relies on manipulation and return of entangled qubits to create a shared key. The protocols that are cryptanalyzed in this paper were proven secure with respect to some eavesdropping approaches, and results reported here do not invalidate these proofs. Rather, they suggest that quantum cryptographic protocols, like conventional protocols, may be vulnerable to methods of attack that were not envisaged by their designers.
NIST Interagency/Internal Report (NISTIR) - 6977
Report Number


access control, authentication, computer security, cryptographic protocols, quantum computing, quantum cryptography


Kuhn, D. (2003), Vulnerabilities in Quantum Key Distribution Protocols, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD (Accessed July 18, 2024)


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Created May 1, 2003, Updated October 16, 2008