Quantum computers can be hacked using classic row-hammer techniques

Classic hacking technique exposes security flaws in quantum computers

Researchers demonstrate how row-hammer-style attacks can disrupt qubit operations on noisy quantum systems

Quantum computers may be governed by the exotic rules of quantum mechanics, but they are not immune to cyberattacks. Two independent research teams have now shown that a classic hacking method, known as a row-hammer attack, can be adapted to exploit vulnerabilities in modern quantum computing platforms—specifically, noisy superconducting qubits accessed via cloud services.

While these findings do not yet suggest a threat to commercial quantum computing, they highlight potential security risks that could arise as the technology scales and multiple users begin sharing quantum resources.

Borrowing a tactic from classical hardware attacks

In traditional computing, row-hammer attacks target DRAM memory, exploiting unintended electrical interference to flip bits and bypass memory protections. In the quantum realm, similar effects can arise due to crosstalk between qubits—the basic units of quantum information.

Researchers at the University of Gdańsk in Poland adapted the row-hammer concept for quantum systems by running rapid, repeated sequences on a group of qubits, inducing crosstalk that unintentionally altered the state of a neighboring qubit on IBM's cloud-accessible quantum computers.

“I was surprised by how strong the crosstalk was in some of the cases,” said project lead Marcin Pawłowski.

Their findings reveal that even physically isolated quantum registers on shared hardware may influence one another under certain conditions.

A second attack: QubitHammer

Simultaneously, a team led by Jakub Szefer at Northwestern University developed QubitHammer, a technique that modifies microwave control pulses to introduce crosstalk across a broader range of qubits—not just adjacent ones.

Tested on another IBM quantum processor, the QubitHammer attack showed that remote qubit registers could be affected by intentionally crafted pulse sequences, raising alarms about multi-tenant quantum architectures in the future.

Could users hack each other in shared quantum systems?

Although IBM has since restricted users' ability to customize microwave pulses, researchers caution that other companies, such as Rigetti Computing and IQM, offer similar cloud-based access to superconducting quantum devices, where hardware-level control remains more open.

“If two users access separate groups of qubits on the same machine, one could potentially disrupt the other’s computations,” says Akshata Shenoy, a researcher from the University of Gdańsk team.

IBM responded by emphasizing that current usage policies prevent simultaneous access by multiple users on the same physical hardware. However, researchers argue that this may not remain the case as cloud quantum computing matures and becomes more cost-efficient through hardware sharing, much like classical cloud infrastructure.

Implications for the future of quantum cybersecurity

These experiments represent an important early warning, say experts. While today’s quantum computers are small and error-prone, techniques like QubitHammer and quantum row-hammer could inform the design of more secure architectures before large-scale machines go mainstream.

“We didn’t build defenses into classical computers until after row-hammer became a threat. Quantum computing gives us a second chance,” said Szefer.

Still, researchers acknowledge that quantum error correction—a developing feature of next-gen machines—may help neutralize such attacks. But history has shown that defensive patches often inspire new attack methods, as was the case with evolving row-hammer variants in classical systems.

“This is just the beginning,” Shenoy adds. “We need to anticipate how adversaries might exploit error mitigation itself.”

A changing definition of quantum hacking

As quantum systems scale and begin integrating into hybrid cloud computing environments, new security definitions will be needed. According to Dominik Hangleiter at UC Berkeley, “quantum hacking” could eventually involve cross-layer attacks, targeting interactions between quantum processors, classical control systems, and distributed software stacks.

For now, the current findings do not pose a practical threat to IBM or other cloud platforms. But they underline the urgency of designing secure protocols and robust hardware safeguards—not after quantum systems become widespread, but before.

Stay tuned to The Horizons Times for the latest on quantum computing, cybersecurity breakthroughs, and the future of cloud-based quantum infrastructure.