A Primer on Security of Quantum Computing Hardware

Quantum computing is an emerging computing paradigm that can potentially transform several application areas by solving some of the intractable problems from classical domain. Similar to classical computing systems, quantum computing stack including software and hardware rely extensively on third parties many of them could be untrusted or less-trusted or unreliable. Quantum computing stack may contain sensitive Intellectual Properties (IP) that requires protection. From hardware perspective, quantum computers suffer from crosstalk that couples two programs in a multi-tenant setting to facilitate traditionally known fault injection attacks. Furthermore, third party calibration services can report incorrect error rates of qubits or mis-calibrate the qubits to degrade the computation performance for denial-of-service attacks. Quantum computers are expensive and access queue is typically long for trusted providers. Therefore, users may be enticed to explore untrusted but cheaper and readily available quantum hardware which can enable stealth of IP and tampering of quantum programs and/or computation outcomes. Recent studies have indicated the evolution of efficient but untrusted compilation services which presents risks to the IPs present in the quantum circuits. The untrusted compiler can also inject Trojans and perform tampering. Although quantum computing can involve sensitive IP and private information and can solve problems with strategic impact, its security and privacy has received inadequate attention. This paper provides comprehensive overview of the basics of quantum computing, key vulnerabilities embedded in the quantum systems and the recent attack vectors and corresponding defenses. Future research directions are also provided to build a stronger community of quantum security investigators.