A group of Chinese cryptographers have shared a thesis on how existing quantum computers can break Rivest–Shamir–Adleman (RSA), a public-key cryptosystem used by blockchains. However, this design is being questioned by some cryptocurrency experts.
372 physical qubits suffice to break RSA-2048
Bao Yan and Ziqi Tang, three researchers from Zhengzhou and Hangzhou, shared a thesis titled “Thesis of Zhengzhou” in December 2022. A superconducting quantum processor can factor integers with sublinear resource. It is a more resource-efficient method of challenging RSA-2048 encryption than ever before.
it’s time to rotate your rsa keys anon pic.twitter.com/meHOdZYpBs
— banteg (@bantg) January 4, 2023
In order to degrade the integrity and security of the above scheme, it was believed that a potential attacker would require millions of physical qubits. This is well beyond current quantum computer hardware capabilities.
The proposed algorithm, however, can overcome these barriers by factoring integers as large as 48 bits with 10 superconducting quibits. This is the largest integer ever factored on any quantum device.
A potential attacker will need 372 physical qubits in order to break the RSA-2048 scheme. In context, QuEra Computing device created by physicists at Harvard MIT and MIT has 256 qubits. IBM’s Condor is expected to surpass the 1,000-qubit mark for 2023.
Experts advise you to relax
However, experts were skeptical about the new reports by Chinese scholars. At one instance, Ethereum (ETH), veteran @dystopiabreaker Suzuha claims that the research is based upon a widely criticized paper.
Their method is based on Schnorr’s “destroyes RSA” paper from a few decades ago. It has been proven to not work well when using larger moduli. It is not clear whether they have overcome this limitation. I am skeptical.
Others experts said that once this attack occurs, the blockchain teams will switch to more secure cryptographic protocols.
Bruce Schneier (prominent computer scientist and lecturer at Harvard Kennedy School) told the media that he didn’t think that “this will break RSA.”