Noisy Intermediate-Scale Quantum (NISQ) quantum computers are being rapidly improved, with bigger numbers of qubits and improved fidelity. The rapidly increasing qubit counts and improving the fidelity of quantum computers will enable novel algorithms to be executed on the quantum computers, and generate novel results and data whose intellectual property will be a highly-guarded secret. At the same time, quantum computers are likely to remain specialized machines, and many will be controlled and maintained in a remote, cloud-based environment where end users who want to come up with novel algorithms have no control over the physical space. Lack of physical control by users means that physical attacks could be possible, by malicious insiders in the data center, for example. This work shows for the first time that power-based side-channel attacks could be deployed against quantum computers. The attacks could be used to recover information about the control pulses sent to quantum computers. From the control pulses, the gate level description of the circuits, and eventually the secret algorithms can be reverse engineered. This work demonstrates how and what information could be recovered, and then in turn how to defend from power-based side-channels. Real control pulse information from real quantum computers is used to demonstrate potential power-based side-channel attacks. Meanwhile, proposed defenses can be deployed already today, without hardware changes.

翻译：噪声中尺度量子计算机正快速演进，其量子比特数量持续增加、保真度不断提升。量子比特数量的快速增长与保真度的持续改善，将使得新型算法得以在量子计算机上执行，并产生具有高度商业机密价值的新型结果与数据。然而，量子计算机仍将保持专用设备的属性，多数情况下需在远程云端环境中进行控制与维护，终端用户在研发新型算法时无法掌控其物理空间。用户对物理空间的失控意味着可能遭受物理攻击，例如数据中心内部恶意人员实施的攻击。本研究首次证明基于电源的侧信道攻击可被应用于量子计算机。此类攻击可窃取发送至量子计算机的控制脉冲信息，进而通过控制脉冲逆向还原电路的逻辑门级描述，最终实现秘密算法的逆向工程。本文系统揭示了可被窃取的信息类型与窃取机制，并提出相应的防御策略。研究中采用真实量子计算机的控制脉冲数据，验证了潜在电源侧信道攻击的可行性，同时提出的防御方案可在不改变现有硬件配置的前提下即刻部署。