标题： SWAP攻击：对多租户量子云系统的隐蔽侧信道攻击 显示英文标题

标题： SWAP Attack: Stealthy Side-Channel Attack on Multi-Tenant Quantum Cloud System

摘要： 量子计算的快速发展推动了广泛的应用，基于云的量子设备在学术界和工业界逐渐受到青睐。 这种转变引发了关于在远程访问的共享多租户量子平台上计算的隐私和安全性的关键担忧。 最近的研究表明，共享量子设备上的串扰使攻击者能够干扰邻近的受害电路。 虽然这些研究有启发性，但关于串扰的根本原因、有效的对策以及在不同电路中的可重复性仍存在未解的问题。 我们重新研究了串扰效应，追溯其根源到量子比特之间的SWAP路径，并证明其影响甚至可以在长距离上显现。 我们的结果显著提升了对这一现象的理解，超越了之前的工作。 提出的基于SWAP的侧信道攻击在主动和被动模式下都能运行，这已在真实的IBM量子设备上得到验证。 在主动攻击中，执行单个CNOT门的攻击者可以干扰正在运行Grover算法的受害电路，通过战略性地放置量子比特，将预期输出准确性降低$81.62\%$。 此外，这种效应可以建模以识别更容易受到攻击的量子比特。 被动攻击利用一个仅为受害者电路大小$6.25\%$的隐蔽电路，在运行Simon算法时实现了$100\%$的准确性来预测受害电路的大小。 这些发现挑战了现有防御策略，即最大化电路之间的拓扑距离，表明攻击者仍然可以远程提取敏感信息或操纵结果。 我们的工作突显了迫切需要强大的安全措施，以保护量子计算免受新兴威胁的影响。 显示英文摘要

摘要： The rapid advancement of quantum computing has spurred widespread adoption, with cloud-based quantum devices gaining traction in academia and industry. This shift raises critical concerns about the privacy and security of computations on shared, multi-tenant quantum platforms accessed remotely. Recent studies have shown that crosstalk on shared quantum devices allows adversaries to interfere with victim circuits within a neighborhood. While insightful, these works left unresolved questions regarding the root cause of crosstalk, effective countermeasures, and replicability across circuits. We revisit the crosstalk effect, tracing its origins to the SWAP path between qubits and demonstrating its impact even over long distances. Our results significantly improve the understanding of this phenomenon beyond prior works. The proposed SWAP-based side-channel attack operates in both active and passive modes, as verified on real IBM quantum devices. In the active attack, an attacker executing a single CNOT gate can perturb victim circuits running Grover's Algorithm, reducing expected output accuracy by $81.62\%$ through strategic qubit placement. Moreover, this effect can be modeled to identify qubits more susceptible to attack. The passive attack, leveraging a stealthy circuit as small as $6.25\%$ of the victim's, achieves $100\%$ accuracy in predicting the victim's circuit size when running Simon's Algorithm. These findings challenge the existing defense strategy of maximizing topological distance between circuits, showing that attackers can still extract sensitive information or manipulate results remotely. Our work highlights the urgent need for robust security measures to safeguard quantum computations against emerging threats.