  Quantum computing offers significant acceleration capabilities over its
classical counterpart in various application domains. Consequently, there has
been substantial focus on improving quantum computing capabilities. However, to
date, the security implications of these quantum computing platforms have been
largely overlooked. With the emergence of cloud-based quantum computing
services, it is critical to investigate the extension of classical computer
security threats to the realm of quantum computing.
  In this study, we investigated timing-based side-channel vulnerabilities
within IBM's cloud-based quantum service. The proposed attack effectively
subverts the confidentiality of the executed quantum algorithm, using a more
realistic threat model compared to existing approaches. Our experimental
results, conducted using IBM's quantum cloud service, demonstrate that with
just 10 measurements, it is possible to identify the underlying quantum
computer that executed the circuit. Moreover, when evaluated using the popular
Grover circuit, we showcase the ability to leak the quantum oracle with a mere
500 measurements. These findings underline the pressing need to address
timing-based vulnerabilities in quantum computing platforms and advocate for
enhanced security measures to safeguard sensitive quantum algorithms and data.
