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arXiv · 1510.03148

Creation of backdoors in quantum communications via laser damage

Vadim Makarov·Jean-Philippe Bourgoin·Poompong Chaiwongkhot·Mathieu Gagné·Thomas Jennewein·Sarah Kaiser·Raman Kashyap·Matthieu Legré·Carter Minshull·Shihan Sajeed
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Abstract

Practical quantum communication (QC) protocols are assumed to be secure provided implemented devices are properly characterized and all known side channels are closed. We show that this is not always true. We demonstrate a laser-damage attack capable of modifying device behaviour on-demand. We test it on two practical QC systems for key distribution and coin-tossing, and show that newly created deviations lead to side channels. This reveals that laser damage is a potential security risk to existing QC systems, and necessitates their testing to guarantee security.

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Vadim Makarov, Jean-Philippe Bourgoin, Poompong Chaiwongkhot, Mathieu Gagné, Thomas Jennewein, Sarah Kaiser, Raman Kashyap, Matthieu Legré, Carter Minshull, Shihan Sajeed. 2016-09-18. Creation of backdoors in quantum communications via laser damage. https://doi.org/10.1103/physreva.94.030302

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