Chaiwongkhot P.Zhong J.Huang A.Qin H.Shi S.c.Makarov V.Mahidol University2023-06-182023-06-182022-12-01EPJ Quantum Technology Vol.9 No.1 (2022)https://repository.li.mahidol.ac.th/handle/20.500.14594/86907We study potential security vulnerabilities of a single-photon detector based on superconducting transition-edge sensor. In one experiment, we show that an adversary could fake a photon number result at a certain wavelength by sending a larger number of photons at a longer wavelength, which is an expected and known behaviour. In another experiment, we unexpectedly find that the detector can be blinded by bright continuous-wave light and then, a controlled response simulating single-photon detection can be produced by applying a bright light pulse. We model an intercept-and-resend attack on a quantum key distribution system that exploits the latter vulnerability and, under certain assumptions, able to steal the key.Physics and AstronomyArticleSCOPUS10.1140/epjqt/s40507-022-00141-22-s2.0-8513760214021960763