G7 Quantum Warning Promotes Safe Migration of Cryptocurrencies

G7 Cybersecurity Working Group calls for immediate transition to anti-quantum cryptography

The G7 Cybersecurity Working Group requires countries and enterprises to immediately begin the transition to anti-quantum cryptography. The warning has direct relevance to cryptographic networks, exchanges and custodians, which must make expensive upgrades to their systems before quantum computers pose a threat to contemporary cryptography.

The working group released "Preparing for the Post-Quantum Era: A Call to Action" on September 3, 2026, which regards quantum computing as a risk to enterprise and cybersecurity, and organizations must prepare before machines with password cracking capabilities appear.

Why a report that does not mention "cryptocurrency" is still closely related to the crypto industry

The G7 report does not explicitly mention cryptocurrency, although the concept is closely linked to blockchain technology. Decrypt pointed out that cryptocurrency transactions and fund management rely on public key cryptography. Although the exact timetable is uncertain, several recent developments suggest that people expect to develop a quantum computer capable of cracking the widely used public-key cryptography mechanism within their reach.

This concern is not limited to future attacks. "Collect now and decrypt later."-- G7 Cybersecurity Working Group. This strategy involves collecting encrypted data today and decrypting it in the future when quantum technology is powerful enough. A similar problem exists in blockchain, because the public key and transaction history may always be visible, putting the key at risk of being hacked in the future.

The G7 recommends that efforts should be made in awareness raising, national policies, research, public-private sector cooperation, and countering quantum procurement requirements.

Europe has set a timetable

Europe has gone further and implemented deadlines. The EU implemented the "Coordinated Implementation Roadmap for the Transition to Anti-Quantum Cryptography" in June 2025. The European Commission's anti-quantum cryptography policy insists that all member states begin the transition by the end of 2026, while high-risk systems must be relocated immediately and completed by 2030. This means that quantum readiness is no longer just a technical issue. As new requirements for quantum-resistant technology become part of procurement and cybersecurity laws, companies without appropriate migration policies may encounter compliance and competitiveness issues.

Bitcoin and Ethereum take different paths

Bitcoin is exploring BIP-360 (Pay-to-Merkle-Root) as a soft fork proposal aimed at reducing the vulnerability of quantum computers to long-term attacks. BIP-360 calls for the abolition of Taproot keypath spending that is susceptible to quantum processing, although its creators acknowledge that faster attacks on memory pool transactions will still depend on the implementation of quantum-resistant digital signatures. An activation date for the BIP-360 has not yet been determined.

Ethereum is building a broader anti-quantum security framework. In his February 2026 roadmap Vitalik Buterin mentioned four components that need to be upgraded: verifier's BLS signature, KZG commitment, ECDSA account signature, and zero-knowledge proof at the application level. Ethereum plans to achieve core quantum-resistant infrastructure by 2029, although the process of migrating to this new technology may still take time.

It is costly. The compact secp256k1 ECDSA signature is about 64 bytes, while the older Dilisium-5 parameter set uses about 4,595 bytes. The ML-DSA standard finalized by NIST uses the ML-DSA-87 signature, accounting for approximately 4,627 bytes. Therefore, an increase in signature size also increases storage, bandwidth, and transaction costs.

The near-term risk lies in the migration itself

Therefore, the immediate market risk is not when a quantum computer will crack Bitcoin, but everything related to it: Governance disputes, protocol development, larger key signatures, infrastructure changes, and old wallets where public keys have been made public.

An article published by Google Quantum AI in March 2026 claimed that cracking 256-bit elliptic curve cryptography consumes much less resources than previously assumed. Google even announced that its system migration will be completed in 2029.

NIST introduced draft IR8547, recommending the phase-out of 112-bit ECDSA after 2030 and banning the use of EDSCA after 2035.

Previously, Cryptopolitan released a report stating that quantum readiness may eventually enter institutional custody standards and investor due diligence standards, which will make network migration plans a competitive advantage.