G7 Warns Quantum Computers Could Break Bitcoin (BTC) Cryptography in New Cyber Report

G7 Cybersecurity Working Group Report

The Group of Seven has formally elevated quantum computing onto the security agenda of its member governments, warning that machines capable of breaking today's public-key encryption may arrive with little notice. In its report, the G7 Cybersecurity Working Group — a forum uniting Canada, France, Germany, Italy, Japan, the United Kingdom and the United States — frames quantum computing not merely as a risk to critical infrastructure but as a security and economic threat to public and private organizations across the board. The document, which we reviewed in full, urges governments and businesses to begin migrating to post-quantum cryptography (PQC), encryption engineered to withstand attacks from both classical and future quantum machines, before a capable quantum computer materializes.

The core of the warning is the harvest-now-decrypt-later problem: data stolen and stored today, even in encrypted form, could be unlocked years from now by a sufficiently powerful quantum computer. The same capability would let attackers forge digital signatures and impersonate users, exposing individual firms and entire supply chains — a break at the cryptographic layer would render wallet-level practices such as blind signing irrelevant, since the signature scheme itself would be compromised. The working group is explicit that timing remains uncertain but preparation cannot wait: “Several recent advances suggest an anticipation of the development of quantum computers able to break widely used public-key cryptography mechanisms,” the report states. It calls the PQC transition a collective effort requiring early engagement and coordinated planning across public and private sectors, recommending that governments fund research, build national PQC strategies and add quantum-security requirements to procurement. Businesses are advised to map critical systems now and swap in quantum-safe products during scheduled upgrades — a path the group says contains costs relative to a wholesale rip-and-replace. Traditionally defensive assets, from gold to government bonds, sit outside this attack surface; anything secured by public-key math does not.

Bitcoin, Ethereum and Solana Weigh Defenses

The report never names cryptocurrency, but the exposure is direct: the same class of public-key cryptography the G7 wants retired protects blockchain wallets and authorizes every transaction on major networks. Today's quantum computers cannot break Bitcoin's cryptography, yet developers across the largest chains are already preparing. Bitcoin improvement proposal BIP-360 is the flagship effort — it would prepare the network to support new post-quantum signature schemes. The harder obstacle is governance rather than code: any major security change to Bitcoin requires broad buy-in from developers, miners, businesses and users, and holders of coins parked in vulnerable legacy addresses would need a way to move funds without interrupting the network.

Ethereum researchers are mapping replacements for the cryptographic components used by accounts, validators and applications, and one recent proposal would rebuild the network's deposit contract — the contract securing staking deposits — to accommodate the larger keys that post-quantum systems demand. The research footprint stretches well beyond signatures, touching the zero-knowledge proofs increasingly used for Ethereum's scaling and verification work. Solana is viewed as having an easier road: the network uses EdDSA signatures, which researchers say simplifies a transition to quantum-resistant alternatives. The Solana Foundation has already tested post-quantum signatures on a test network and shipped an optional hash-based vault for protecting funds — a notable step for an ecosystem spanning consumer integrations like Solana Blinks and Actions to institutional flows. Readers tracking the market in real time can follow live spot and futures prices on Binance.

Coordination Is the Real Bottleneck

The load-bearing document here is the G7 report itself — a primary intergovernmental publication, not market chatter — and its most consequential admission is that the timeline is unknown. Our reading at COINOTAG: crypto's quantum exposure is a coordination problem before it is a cryptography problem. The mathematics of PQC already exists; what Bitcoin, Ethereum and Solana each lack is a fast mechanism for pushing a signature-scheme change through decentralized governance while safely migrating old addresses. The G7's cost-containment advice — adopt quantum-safe primitives during scheduled upgrades — maps awkwardly onto networks that upgrade by social consensus. BIP-360 and Ethereum's deposit-contract proposal will be the first real test cases.