Comment on “quantum oblivious transfer: a secure practical implementation”

Abstract

We study the entanglement-based attack on a recently proposed quantum oblivious transfer (OT) protocol (Nagy and Nagy in Quantum Inf Process 15:5037, 2016). While in secure OT, Bob’s probability of obtaining Alice’s secret bit unambiguously should be limited to $50\%$, we show that if Bob has the technology to handle 5-body entangled states in the current protocol, then he can increase this probability to $64.6\%$. More importantly, in contrast to what the authors claimed, increasing the number of qubits used in the protocol cannot increase the hardness of Bob’s attack.