Quantum computers have serious security flaws? Here's what researchers warn

New research from Penn State University found that quantum computers are exposed to serious security risks, despite the promise to revolutionise science and industry with their unmatched processing power. Researchers also said that securing quantum computers requires more than protecting software, adding that it must also be treated as a critical part of any defence strategy.

"Quantum computers are expected to deliver extraordinary speed and computing power, with the potential to transform scientific research and business operations. That same power also makes them especially appealing targets for cyberattacks," said Swaroop Ghosh, a professor of computer science and electrical engineering at the Penn State School of Electrical Engineering and Computer Science.

“Quantum computers need to be safeguarded from the ground up. At the device level, developers should focus on mitigating crosstalk and other sources of noise -- external interference -- that may leak information or impede effective information transfer. At the circuit level, techniques like scrambling and information encoding must be used to protect the data built into the system. At the system level, hardware needs to be compartmentalised by dividing business data into different groups, granting users specific access based on their roles and adding a layer of protection to the information. New software techniques and extensions need to be developed to detect and fortify quantum programs against security threats,” he added.

He said, unlike traditional computers, which rely on bits that exist as either zero or one, quantum computers operate using quantum bits, or qubits. These qubits can exist as zero, one or both at the same time through a phenomenon known as superposition. They can also be linked through entanglement, allowing quantum machines to process exponentially larger amounts of data compared with classical systems.

This capability makes quantum computers highly attractive for industries such as pharmaceuticals, where they could dramatically speed up drug discovery and development. However, the same complexity introduces unique security challenges.

Interconnected qubits and unwanted interactions

Meanwhile, another researcher from the university, Suryansh Upadhyay, claimed that there is currently no efficient way to verify the integrity of quantum programs and compilers, many of which are developed by third parties. This leaves sensitive corporate and personal data vulnerable to theft or manipulation. He also warned that intellectual property is often embedded directly into quantum circuits, meaning exposed circuits could allow attackers to extract proprietary algorithms, financial data or even critical infrastructure details.

Another risk stems from the very feature that gives quantum computers their power: interconnected qubits. Unwanted interactions, known as crosstalk, can leak information or disrupt computations, especially when multiple users share the same quantum processor. "Since quantum computers are still a relatively new technology, there is not much incentive for attackers to target them, but as the computers are integrated into industry and our day-to-day life, they will become a prime target," Upadhyay said.

The researchers argued that current cybersecurity techniques, which are used in classical computing, are largely ineffective for quantum systems. They added that the commercial providers are currently focused on making quantum computers reliable rather than secure, leaving critical assets such as circuit designs and encoded data without full protection.

In order to solve these risks, Ghosh said security must be designed into quantum computers from the ground up. This includes reducing noise and crosstalk at the hardware level, protecting data at the circuit level using encoding and scrambling, and compartmentalising information at the system level. In addition, he highlighted that new software tools will also be required to detect and counter emerging quantum-specific threats as the technology moves closer to widespread use.