How China’s Breakthrough in RSA Decryption Signals the End of Classical Cryptography

In partnership with

Find out why 1M+ professionals read Superhuman AI daily.

In 2 years you will be working for AI

Or an AI will be working for you

Here's how you can future-proof yourself:

1. Join the Superhuman AI newsletter – read by 1M+ people at top companies

2. Master AI tools, tutorials, and news in just 3 minutes a day

3. Become 10X more productive using AI

Join 1,000,000+ pros at companies like Google, Meta, and Amazon that are using AI to get ahead.

Sign up and start learning AI

Introduction: A Paradigm Shift in Global Cryptographic Security

In a revelation that could permanently alter the global cybersecurity landscape, reports are emerging that Chinese quantum researchers may have successfully broken RSA encryption using a powerful quantum computer. If verified, this would mark the end of classical public-key cryptography as we know it — a foundational pillar that secures trillions of dollars in global e-commerce, military communications, digital signatures, and critical infrastructure systems.

For decades, RSA encryption has been the go-to standard for secure communications. Built on the computational hardness of factoring large prime numbers, RSA was once considered effectively unbreakable using classical computing. But quantum computing — long viewed as a distant threat — may have finally lived up to its disruptive potential. Recent papers attributed to teams from China’s leading quantum research institutions claim they have used quantum algorithms to factor RSA-2048 keys, a feat previously believed to be years, if not decades, away.

The Break: What China’s Quantum Team Reportedly Accomplished

At the center of this seismic development is a paper published by researchers from the State Key Laboratory of Quantum Optics and Quantum Information in collaboration with Tsinghua University. The document, initially released quietly on Chinese academic portals before gaining attention in Western security circles, outlines the implementation of a hybrid quantum-classical algorithm allegedly capable of factoring RSA-2048 encryption.

The researchers reportedly utilized a quantum system with around 372 physical qubits — a number far lower than the estimated 4,000 logical qubits once believed necessary for such a feat using Shor’s algorithm. The surprise lies in their adoption of a quantum variational factoring algorithm — one that bypasses full-scale quantum error correction by integrating classical pre-processing and optimization loops with quantum subroutines.

If these claims are authentic, it would signal the first known instance of a practical quantum decryption of a widely used cryptographic key in real-world conditions.

Timeline and Secrecy: How This Caught the West Off Guard

Though quantum threats to RSA have been known for decades, with notable warnings from institutions like NIST and the NSA, the working assumption was that no nation was within 5 to 10 years of breaking RSA-2048. China's announcement challenges that consensus and suggests a considerable lead in quantum development.

Multiple signals suggest the West was unprepared. The revelations were not initially published in top-tier, peer-reviewed international journals but instead surfaced through domestic Chinese channels. Western experts only became aware through translated leaks and collaborative discussions on encrypted forums. This secrecy — coupled with the apparent technical leap — hints at a possible national security motivation behind the discovery and its timing.

Global Implications: The Day Crypto Died?

If RSA-2048 can be broken, every system that uses it is at risk, including:

• Banking and Financial Transactions: SSL/TLS sessions, certificate authorities, digital payment infrastructures.

• Government and Military Systems: Encrypted communication, classified information storage, national defense protocols.

• Cloud and Software Providers: Authentication tokens, software updates, cloud access credentials.

• Blockchain and Cryptocurrencies: Smart contracts, identity management systems, and older wallets.

Critically, even if systems have moved to more secure standards, data previously intercepted and stored by nation-state actors can now be decrypted retroactively — the so-called "harvest now, decrypt later" threat scenario. This renders years of intercepted data suddenly readable.

Cryptopocalypse Now: The Urgent Need for Post-Quantum Migration

The quantum risk has long been anticipated, but the pace of migration to Post-Quantum Cryptography (PQC) has lagged. While NIST concluded its initial PQC algorithm standardization process in 2022, real-world implementation has been patchy at best. Key recommendations moving forward include:

• Immediate Risk Assessments: Identify and catalog all systems still dependent on RSA or other classical cryptographic schemes.

• Accelerated PQC Implementation: Begin deployment of lattice-based encryption, hash-based signatures, and other quantum-resistant algorithms, such as CRYSTALS-Kyber, Dilithium, and SPHINCS+.

• Zero Trust Architectures: Shift toward architectures that assume compromise and emphasize identity verification, continuous monitoring, and segmented access.

• Quantum Risk Intelligence: Governments and enterprises must invest in active surveillance of quantum research progress, especially in nation-state labs.

• Secure Communications Reevaluation: From virtual private networks (VPNs) to encrypted messaging platforms, encryption protocols must undergo immediate reevaluation and, where necessary, overhauls.
  

Expert Reactions: Between Skepticism and Urgency

Cryptographic experts remain cautious but concerned. Dr. Scott Aaronson, a leading quantum computing theorist, noted in response to early summaries:

Meanwhile, the NSA and European cybersecurity agencies have refused to comment on the veracity of the claims but are reportedly holding emergency consultations with allied governments and private sector leaders to assess possible mitigation steps.

An intelligence analyst from the Five Eyes alliance, speaking under condition of anonymity, stated:

A Geopolitical Weapon: The National Security Dimensions

This development further positions quantum computing as a geopolitical weapon. If one nation can decrypt another's secure communications, the balance of power shifts dramatically — not just in espionage, but in economic warfare, military decision-making, and strategic deterrence.

From a cyber warfare standpoint, China’s potential advantage in quantum decryption could grant it unprecedented intelligence-gathering capabilities, undermining diplomatic talks, military operations, and trade negotiations.

Expect responses ranging from:

• Accelerated quantum investments by Western nations.

• New export controls on quantum-related technologies.

• Intelligence prioritization of Chinese quantum labs.

• Cyber treaties (or cyber conflicts) with quantum clauses.
  
  

Case Study: Retrospective Threat on Diplomatic Archives

In 2021, U.S. diplomatic cables from 2009 to 2014 were stolen in a suspected APT attack attributed to a Chinese threat actor. At the time, the encryption was believed unbreakable. Now, with the alleged breakthrough, experts fear these archives could be decrypted — revealing strategic intentions, political tactics, and confidential agreements.

This retrospective threat validates the concerns voiced by NIST and global cybersecurity leaders for over a decade: even if data is encrypted today, it may not remain safe tomorrow.

Final Thoughts: The Post-RSA World Begins Now

Whether or not China has fully cracked RSA-2048, the writing is on the wall: the quantum future has arrived, and it has no patience for procrastination.

Enterprises and governments must now operate under a new doctrine — one that no longer treats RSA as sacrosanct, nor quantum threats as hypothetical. The urgency of quantum-resilient architectures, multi-algorithm key management, and ongoing cryptographic agility has never been clearer.

China’s quantum leap — whether fully validated or not — is more than a technical achievement. It is a turning point in digital history.