G7 Central Banks' First Report: Quantum Computers Will Crack Modern Cryptography Within 10 Years! Warns of a Systemic Crisis of "Harvest First, Decrypt Later"

G7 Central Bank Quantum Technology Working Group (QTWG) releases its first public report today (15th), providing a comprehensive analysis of the double-edged sword effect of quantum computing on global digital finance. The report sternly warns that quantum computers capable of decryption may emerge within the next 10 years, and the strategy of "harvest now, decrypt later" by hackers will pose significant systemic threats to the global financial system, urging central banks and financial institutions worldwide to accelerate defense upgrades.
(Background: Quantinuum Quantum IPO subscription exceeds expectations: raising the offering price by 10%, valuation surges to $14 billion, listed on 6/4)
(Additional context: How long until Bitcoin is broken by quantum computers? Google reveals the cracking threshold has dropped 20 times, experts worry governance crises could become fatal)

Table of Contents

Toggle

• "Harvest now, decrypt later" becomes the biggest threat
• Double-edged sword effect: optimizing risk assessment and macro forecasts
• Senior central bank officials jointly call: the window for quantum preparedness is closing

The underlying security logic of the global financial system is facing unprecedented technological challenges. Led by the French Central Bank and the Bank of Canada, and gathering authoritative institutions such as the Federal Reserve (Fed), the European Central Bank (ECB), the Bank of Japan, and the Bank of England, the "G7 Central Bank Quantum Technology Working Group (QTWG)" officially published its first public report titled "Preparing for Quantum Technology: Key Considerations for Financial Sector Participants" on June 15, 2026. This report not only marks the strategic stance of G7 countries on quantum risks but also issues a warning for the global digital financial defense transition period.

"Harvest now, decrypt later" becomes the biggest threat

The report points out that although there are currently no quantum computers with cryptographic relevance capable of cracking modern cryptography, experts generally estimate that this technological breakthrough could occur within the next 10 years. At that time, traditional encryption algorithms widely used to protect financial transactions, cross-border communications, and ledger records will be vulnerable in the face of quantum computing power.

What worries central bank leaders even more is a potential attack strategy called "harvest now, decrypt later." Malicious actors are likely intercepting and hoarding encrypted data that cannot be cracked today, waiting for future quantum technology to mature for decryption. This long-term confidentiality attack strategy poses a deadly systemic risk to highly interconnected global financial networks. If institutions are unprepared to varying degrees, it could easily trigger chain reaction failures.

Double-edged sword effect: optimizing risk assessment and macro forecasts

However, quantum technology is not only destructive. The report neutrally assesses the significant transformative opportunities this technology brings. In financial applications, quantum computing shows potential to outperform traditional supercomputers in extreme optimization, complex simulations, and massive data modeling. In the future, these techniques could be deeply integrated into portfolio optimization, large-scale stress testing, real-time risk assessment, and even revolutionize macroeconomic forecasting models.

But the G7 report also reminds that these tangible financial benefits heavily depend on the commercial scalability and empirical value of quantum technology. The introduction of new technology may also lead to risks of excessive computational power concentration and governance challenges.

Senior central bank officials jointly call: the window for quantum preparedness is closing

Faced with this silent technological revolution, the G7 working group has not issued mandatory regulatory prescriptions but strongly recommends that major financial institutions immediately conduct internal audits, assess their current reliance on traditional cryptography, and stay aligned with the G7 post-quantum cryptography (PQC) migration roadmap, advancing cross-institutional technical testing.

Tiff Macklem, Governor of the Bank of Canada, emphasized when discussing the report: "The window for quantum preparedness in the financial industry is rapidly closing. We must ensure the resilience and security of the system." Agnès Bénassy-Quéré, Vice President of the French Central Bank, also stressed that central banks have an absolute responsibility to foresee and guide this potentially profound transformation affecting global financial stability.