Generalized efficiency mismatch attack to bypass the detection-scrambling countermeasure
M A Ruhul Fatin, Shihan Sajeed · Optics Express · 2021
The ability of an eavesdropper to compromise the security of a quantum communication system by changing the angle of the incoming light is well-known. Randomizing the role of the detectors has been proposed to be an efficient countermeasure to this type of attack. Here we show that the proposed countermeasure can be bypassed if the attack is generalized by including more attack variables. Using the experimental data from existing literature, we show how randomization effectively prevents the initial attack but fails to do so when Eve generalizes her attack strategy. Our result and methodology could be used to scrutinize a free-space quantum communication receiver against detector-efficiency-mismatch type attacks.