Quantum Trojan-Horse Attack (THA)

The Quantum Trojan-Horse Attack (THA), also known as the "Large Pulse Attack" or "Backflash Attack," is a sophisticated attack in quantum communication systems where a threat actor (Eve) exploits the return path of quantum signals to gain information. This method involves sending bright pulses to the legitimate receiver and analyzing the back-reflected signals to extract key information without detection.


Literature

[Gisin2006] N. Gisin, S. Fasel, B. Kraus, H. Zbinden, and G. Ribordy. "Trojan-horse attacks on quantum-key-distribution systems" In: Phys. Rev. A, vol. 73, no. 2, p. 022320. (2006) 10.1103/PhysRevA.73.022320.
[Jain2014] N. Jain, E. Anisimova, I. Khan, V. Makarov, C. Marquardt, and G. Leuchs. "Trojan-horse attacks threaten the security of practical quantum cryptography" In: New J. Phys., vol. 16, no. 12, p. 123030. (2014) 10.1088/1367-2630/16/12/123030.
[Jain2015] N. Jain, B. Stiller, I. Khan, V. Makarov, C. Marquardt, and G. Leuchs. "Risk Analysis of Trojan-Horse Attacks on Practical Quantum Key Distribution Systems" In: IEEE Journal of Selected Topics in Quantum Electronics, vol. 21, no. 3, pp. 168–177. (2015) 10.1109/JSTQE.2014.2365585.
[Vakhitov2001] A. Vakhitov, V. Makarov, and D. R. Hjelme. "Large pulse attack as a method of conventional optical eavesdropping in quantum cryptography" In: Journal of Modern Optics, vol. 48, no. 13, pp. 2023–2038. (2001) 10.1080/09500340108240904.

QID: A-0049
Tier: T0
Type: Quantum
Tactic: Execution
Created: 2024-01-30
Updated: 2024-08-12

Technique → Countermeasures

List of countermeasures applicable to this technique.

Items: 5
Description Countermeasure

Application of privacy amplification in the case of partial key leakage.

Monitoring of incoming pulses at the transmitter party.

Monitoring of the detector for unusual signals.

Employment of optical isolation at the transmitter party.

Employment of optical isolation at the transmitter and receiver party.