Quantum Computer Breaks 22-Bit RSA Encryption: A Haunting Signal for Data Security

Chinese researchers from Shanghai University have utilized a quantum computer to factor a 22-bit integer within the RSA encryption algorithm. Earth reported this in connection with the study they published.

The authors stated, «By using the D-Wave Advantage device, we successfully factored a 22-bit integer in RSA, showcasing the potential of quantum machines to tackle cryptographic challenges.»

Previously, this algorithm had resisted attempts to breach it on similar equipment.

Although 22-bit keys are not secure by today’s standards and can be factored using classical systems, this is the largest integer successfully factored via quantum annealing to date.

Most modern security systems employ 2048-bit encryption, while the largest key cracked using traditional methods was only 829 bits (RSA-250), which took several weeks of computation on a supercomputer to decode.

In factoring the 22-bit RSA key, the researchers employed the same method used to successfully decrypt the Present, Gift-64, and Rectangle algorithms in October 2024. They described this breakthrough as «the first instance where a real quantum computer poses a significant threat to several large-scale structured algorithms.»

Despite the trivial size of the 22-bit key compared to industrial-grade RSA, the test is significant as the methodology scales beyond previous studies which were limited to 19 bits and needed more qubits per variable.

According to the article, reducing local field coefficients and connections in the Ising model diminishes noise, allowing the annealer to reach the correct coefficients more frequently and suggesting pathways for larger keys.

Universal gate-based quantum machines operate using Shor’s algorithm, which theoretically could «break» RSA by finding the period of modular exponentiation in polynomial time. However, such devices struggle with error correction and require a substantial number of qubits.

To streamline the process, the Chinese researchers opted for annealing instead of Shor’s method. This approach shifted the task from finding the period of a number to identifying the value itself, circumventing current limitations regarding qubit quantity, but at the cost of exponential scaling, which is why only a 22-bit modulus was achieved.

While RSA with larger keys remains secure, this research indicates that advancements in hardware and computational optimization already pose a threat.

Many organizations, including banks and other entities reliant on encryption, have yet to upgrade their cryptographic resources, according to Earth journalists. Additionally, many remain unaware of the algorithms their systems depend on.

Entities that have stored sensitive information, medical records, financial documents, and diplomatic communications for decades could face significant risks by delaying the transition to full-scale quantum computing.

Although cracking the 22-bit RSA relied on extensive pre-processing and post-processing, and the annealing process required many runs to achieve the desired values, cryptographers advise firms and institutions to begin formulating plans to transition to new algorithms.

Furthermore, “intermediate” breaches of encryption systems could already pose a considerable security threat. Therefore, it is recommended to use combined data protection methods.

It is worth noting that Tether has predicted a breach and the recovery of bitcoins associated with Satoshi Nakamoto.