As quantum computing paradigms merge with machine learning models, a new threat emerges: reverse engineering attacks that can expose sensitive parameters and proprietary algorithms embedded within these models. Researchers have found that multi-qubit classifiers can be vulnerable to such attacks, allowing adversaries to exploit weaknesses in the model’s architecture and parameters. This raises serious concerns about the security of Quantum Machine Learning (QML) models, particularly against white-box access during inference.
The Quantum Imitation Game: A Threat to Secure Machine Learning
Integrating quantum computing paradigms with machine learning models, known as Quantum Machine Learning (QML), has significant potential for solving complex problems. However, with the proliferation of third-party vendors in the Noisy Intermediate-Scale Quantum (NISQ) era, the security of QML models becomes a pressing concern, particularly against reverse engineering.
Reverse engineering (RE) is a powerful attack model that can expose sensitive parameters and proprietary algorithms embedded within QML models. An adversary with white-box access to the transpiled version of the user-designed trained QML model during inference can steal and use the model without modification. However, extracting the pre-transpiled copy of the QML circuit will enable retranspilation and usage on various hardware with different native gate sets and qubit technology.
The information about parameters, such as their placements and optimized values, can allow further training of the QML model if the adversary plans to alter the model. This could be used to tamper with the watermark or embed a new watermark, refine the model for other purposes, or even use it for malicious activities.

performed by the untrusted vendor to extract the parameters and steal the IP of the user-designed model.
Investigating Reverse Engineering of Quantum Classifiers
In this first effort to investigate the RE of QML circuits, researchers examined quantum classifiers by comparing the training accuracy of original and reverse-engineered models across various sizes. The study focused on Quantum Neural Networks (QNNs) with different numbers of qubits and parametric layers.
The results showed that multi-qubit classifiers can be reverse-engineered under specific conditions, with a mean error of order 10^-2 in a reasonable time. This highlights the vulnerability of QML models to RE attacks. The study also proposed adding dummy rotation gates in the QML model with fixed parameters to increase the RE overhead for defense.
For instance, adding 2 dummy qubits and 2 layers increases the overhead by 176 times for a classifier with 2 qubits and 3 layers, with a performance overhead of less than 9. This suggests that incorporating dummy gates can defend against RE attacks.
The Power of Reverse Engineering
The study emphasizes that RE is a very powerful attack model that warrants further efforts on defenses. As QML models become increasingly complex and widespread, the risk of RE attacks grows. Developing robust security measures to protect sensitive parameters and proprietary algorithms embedded within these models is essential.
Quantum Machine Learning: A New Era in Computing
Quantum Machine Learning (QML) represents a new era in computing, where quantum computing paradigms are combined with machine learning models. This integration has significant potential for solving complex problems that were previously unsolvable or required extensive computational resources.
However, the security of QML models is a pressing concern, particularly against RE attacks. As third-party vendors proliferate in the NISQ era, the risk of RE attacks grows. It is essential to develop robust security measures to protect sensitive parameters and proprietary algorithms embedded within these models.
The Importance of Secure Quantum Machine Learning
The secure development and deployment of QML models are crucial for their widespread adoption. As QML models become increasingly complex and widespread, the risk of RE attacks grows. It is essential to develop robust security measures to protect sensitive parameters and proprietary algorithms embedded within these models.
The study highlights the importance of addressing the security concerns associated with QML models. By developing robust defenses against RE attacks, researchers can ensure that QML models are secure and reliable for various applications.
Quantum Classifiers: A Key Component in Machine Learning
Quantum classifiers are a key component in machine learning, particularly in QML models. These classifiers have the potential to solve complex problems that were previously unsolvable or required extensive computational resources.
However, as the study shows, quantum classifiers can be vulnerable to RE attacks. The results highlight the importance of developing robust security measures to protect sensitive parameters and proprietary algorithms embedded within these models.
Defenses Against Reverse Engineering Attacks
The study proposes adding dummy rotation gates in the QML model with fixed parameters to increase the RE overhead for defense. This approach has shown promise, with an addition of 2 dummy qubits and 2 layers increasing the overhead by 176 times for a classifier with 2 qubits and 3 layers.
This suggests that incorporating dummy gates can provide a viable defense against RE attacks. However, further research is needed to develop more robust security measures that can protect QML models from RE attacks.
Conclusion
The study highlights the importance of addressing the security concerns associated with QML models. By developing robust defenses against RE attacks, researchers can ensure that QML models are secure and reliable for various applications.
As QML models become increasingly complex and widespread, the risk of RE attacks grows. It is essential to develop robust security measures to protect sensitive parameters and proprietary algorithms embedded within these models. The study emphasizes that RE is a very powerful attack model that warrants further efforts on defenses.
Publication details: “The Quantum Imitation Game: Reverse Engineering of Quantum Machine Learning Models”
Publication Date: 2024-11-19
Authors: Archisman Ghosh and Swaroop Ghosh
Source:
DOI: https://doi.org/10.1145/3689939.3695783
