On the Security of Two Blind Quantum Computations

TL;DR

This paper critically examines two existing blind quantum computation protocols, revealing security vulnerabilities that could allow servers to access client information, thus highlighting the need for more secure BQC designs.

Contribution

The paper identifies and analyzes security loopholes in two prominent BQC protocols, demonstrating potential privacy breaches and emphasizing the importance of rigorous security proofs.

Findings

Security loophole in Li et al.'s triple-server protocol

Security loophole in Xu et al.'s single-server protocol

Potential for server to reveal client private information

Abstract

Blind quantum computation (BQC) protocol allows a client having partial quantum ability to delegate his quantum computation to a remote quantum server without leaking any information about the input, the output and the intended computation to the server. Several BQC protocols have been proposed, e.g., Li et al. in [1] proposed a triple-server BQC protocol and Xu et al. in [2] proposed a single-server BQC protocol. Though both papers claimed that their protocols can satisfy the requirement of privacy, this paper points out a security loophole in their protocols. With that the server can reveal the private information of the client.