Quantum computing often requires classical data to be supplied to execution environments that may not be fully trusted or isolated. While encryption protects data at rest and in transit, it provides limited protection once computation begins, when classical values are encoded into quantum registers. This paper explores data obfuscation for protecting classical values during quantum computation. To the best of our knowledge, we present the first explicit data obfuscation technique designed to protect classical values during quantum execution. We propose an obfuscation technique that encodes sensitive data into structured quantum representations across multiple registers, avoiding direct exposure while preserving computational usability. Reversible quantum operations and amplitude amplification allow selective recovery of valid encodings without revealing the underlying data. We evaluate the feasibility of the proposed method through simulation and analyze its resource requirements and practical limitations. Our results highlight data obfuscation as a complementary security primitive for quantum computing.
Quantum computing often requires classical data to be supplied to execution environments that may not be fully trusted or isolated. While encryption protects data at rest and in transit, it provides limited protection once computation begins, when classical values are encoded into quantum registers. This paper explores data obfuscation for protecting classical values during quantum computation. To the best of our knowledge, we present the first explicit data obfuscation technique designed to protect classical values during quantum execution. We propose an obfuscation technique that encodes sensitive data into structured quantum representations across multiple registers, avoiding direct exposure while preserving computational usability. Reversible quantum operations and amplitude amplification allow selective recovery of valid encodings without revealing the underlying data. We evaluate the feasibility of the proposed method through simulation and analyze its resource requirements and practical limitations. Our results highlight data obfuscation as a complementary security primitive for quantum computing.
Quantum computing often requires classical data to be supplied to execution environments that may not be fully trusted or isolated. While encryption protects data at rest and in transit, it provides limited protection once computation begins, when classical values are encoded into quantum registers. This paper explores data obfuscation for protecting classical values during quantum computation. To the best of our knowledge, we present the first explicit data obfuscation technique designed to protect classical values during quantum execution. We propose an obfuscation technique that encodes sensitive data into structured quantum representations across multiple registers, avoiding direct exposure while preserving computational usability. Reversible quantum operations and amplitude amplification allow selective recovery of valid encodings without revealing the underlying data. We evaluate the feasibility of the proposed method through simulation and analyze its resource requirements and practical limitations. Our results highlight data obfuscation as a complementary security primitive for quantum computing.
The developments in quantum computing hardware and software are focused on boosting the scalability and robustness of quantum systems. With near-term quantum computers poised to accelerate specific computational tasks, ensuring their security has become a pressing priority. Recent efforts have proposed practical solutions to ensure data confidentiality in quantum computers accessed through the cloud, particularly in the presence of untrusted quantum cloud providers by leveraging trusted hardware that enables quantum circuit obfuscation. However, these solutions overlook the detailed structural information of the quantum algorithms, which may limit the effectiveness of the obfuscation methods. In this paper, we investigate the structural constraints of quantum algorithms executed across different quantum architectures. Based on this analysis, we develop a Machine Learning (ML)-based classifier that reveals the underlying quantum algorithm of the obfuscated physical quantum circuit. We also propose a pre-processing phase to minimize the obfuscation's impact on the classifier accuracy. We evaluate our proposed ML-based classification model on different obfuscated physical quantum circuits, which are transpiled to support IBM quantum hardware. Our analysis shows the vulnerability of existing obfuscation methods to reverse engineering attacks, which can potentially expose sensitive information about quantum circuits.
This paper introduces ObfusQate, a novel tool that conducts obfuscations using quantum primitives to enhance the security of both classical and quantum programs. We have designed and implemented two primary categories of obfuscations: quantum circuit level obfuscation and code level obfuscation, encompassing a total of eight distinct methods. Quantum circuit-level obfuscation leverages on quantum gates and circuits, utilizing strategies such as quantum gate hiding and identity matrices to construct complex, non-intuitive circuits that effectively obscure core functionalities and resist reverse engineering, making the underlying code difficult to interpret. Meanwhile, code-level obfuscation manipulates the logical sequence of program operations through quantum-based opaque predicates, obfuscating execution paths and rendering program behavior more unpredictable and challenging to analyze. Additionally, ObfusQate can be used to obfuscate malicious code segments, making them harder to detect and analyze. These advancements establish a foundational framework for further exploration into the potential and limitations of quantum-based obfuscation techniques, positioning ObfusQate as a valuable tool for future developers to enhance code security in the evolving landscape of software development. To the best of our knowledge, ObfusQate represents the pioneering work in developing an automated framework for implementing obfuscations leveraging quantum primitives. Security evaluations show that obfuscations by ObfusQate maintain code behavior with polynomial overheads in space and time complexities. We have also demonstrated an offensive use case by embedding a keylogger into Shor's algorithm and obfuscating it using ObfusQate. Our results show that current Large language models like GPT 4o, GPT o3 mini and Grok 3 were not able to identify the malicious keylogger after obfuscation.
We introduce ObfusQate, a novel framework that performs software obfuscation using quantum primitives to enhance the security of both classical and quantum programs. ObfusQate implements eight obfuscation techniques categorized into quantum circuit-level and code-level transformations. Circuit-level obfuscation leverages quantum gates, identity operations, and unitary transformations to construct non-intuitive circuits that resist reverse engineering. Code-level obfuscation employs quantum-based opaque predicates to obscure control flow, making execution paths unpredictable. We evaluate the effectiveness of ObfusQate using three benchmark quantum algorithms: Bernstein-Vazirani, Shor’s, and QAOA. Experiments show that the framework incurs tunable polynomial overhead in both time and space, while preserving functional correctness. Additionally, we demonstrate an offensive use case by embedding a keylogger into Shor’s algorithm. Large language models (GPT-4o, GPT-o3-mini, and Grok-3) successfully identified the payload in the unobfuscated version, but failed when it was obfuscated using ObfusQate. To our knowledge, ObfusQate is the first automated system for quantum software obfuscation. It provides a foundation for secure deployment of quantum software in adversarial and shared environments.
Quantum computing leverages quantum mechanics to achieve computational advantages over classical hardware, but the use of third-party quantum compilers in the Noisy Intermediate-Scale Quantum (NISQ) era introduces risks of intellectual property (IP) exposure. We address this by proposing a novel obfuscation technique that protects proprietary quantum circuits by inserting additional quantum gates prior to compilation. These gates corrupt the measurement outcomes, which are later corrected through a lightweight classical post-processing step based on the inserted gate structure. Unlike prior methods that rely on complex quantum reversals, barriers, or physical-to-virtual qubit mapping, our approach achieves obfuscation using compiler-agnostic classical correction. We evaluate the technique across five benchmark quantum algorithms—Shor’s, QAOA, Bernstein-Vazirani, Grover’s, and HHL—using IBM’s Qiskit framework. The results demonstrate high Total Variation Distance (above 0.5) and consistently negative Degree of Functional Corruption (DFC), confirming both statistical and functional obfuscation. This shows that our method is a practical and effective solution for the security of quantum circuit designs in untrusted compilation flows.
Circuit cutting is a novel technique in the field of quantum computing that offers a promising approach for breaking up large quantum circuits into smaller ones that can be executed on smaller quantum computers. Circuit cutting offers a scalable and hybrid computing approach, by combining classical and quantum computers to run large quantum circuits. At the same time, quantum circuits represent the fundamental building blocks of quantum algorithms, and obfuscation techniques are crucial for protecting the sensitive information and intellectual property encoded in these circuits. This paper constitutes the first security analysis of circuit cutting techniques as a means to protect quantum circuits, and not just for cutting bigger quantum circuits to fit on smaller devices. As cloud providers are in control of quantum computers and give access to users, utilizing cloud-based quantum computers for executing quantum circuits involves considerable security risks. This work demonstrates that quantum circuits can be effectively obfuscated by using quantum circuit cutting techniques. If users are worried about an adversary who attempts to reverse-engineer the original quantum algorithm, circuit cutting can be used as a security measure. To further provide configurable obfuscation level, i.e. number of possible circuits that the cloud provider would have to guess, this work proposes a novel dummy-subcircuits technique. This technique introduces dummy subcircuits with additional qubit cut points to create more confusion for the cloud provider and further help to obfuscate the user's original circuits with limited cost.