G7 Warns of Quantum Cyberattack Threat, Urges Post-Quantum Cryptography Adoption

The G7 is urging governments and businesses to prepare for quantum-enabled cyberattacks now, warning that migration could take years and that sensitive data is already at risk.

In a new report, the cybersecurity working group of the Group of Seven, better known as the G7—a forum comprising Canada, France, Germany, Italy, Japan, the United Kingdom and the United States—called quantum computing a security and economic threat to public and private organizations, not just critical infrastructure operators.

“Although the exact timeline is uncertain, several recent advances suggest an anticipation of the development of quantum computers able to break widely used public-key cryptography mechanisms and threaten the security of digital infrastructures,” the group wrote.

The group urged organizations to adopt post-quantum cryptography, or PQC, to protect against classical and quantum attacks. Without it, data stolen and stored today could later be decrypted by a sufficiently powerful quantum computer, which could also break digital signatures, enable impersonation, and expose companies and their supply chains.

“We acknowledge that transitioning to PQC is not a problem for individual organizations to solve in isolation, but rather a collective transition that can only be achieved with early engagement, coordinated planning, and informed decision-making across the public and private sectors,” wrote.

While the report does not mention cryptocurrency, the same class of public-key cryptography protects blockchain wallets and authorizes transactions.

Current quantum computers cannot break Bitcoin’s cryptography. Developers are nevertheless considering post-quantum proposals including BIP-360, which would prepare the network to support new signature schemes.

Bitcoin’s governance makes the transition more complicated. Any major security change would require broad support from developers, miners, businesses, and users. Bitcoin holders would also need a way to move funds from vulnerable addresses without disrupting the network.

Ethereum researchers are planning replacements for several cryptographic components used by accounts, validators, and applications. One recent proposal would rebuild Ethereum’s deposit contract to support the larger keys required by post-quantum systems.

Solana may have a simpler migration path because it uses EdDSA signatures, researchers have said. The Solana Foundation has tested post-quantum signatures on a test network and introduced an optional hash-based vault for protecting funds.

The G7 Cybersecurity Working Group urged governments to support research, public-private partnerships and national PQC strategies while adding quantum security to procurement requirements. It also advised organizations to identify critical systems and adopt quantum-safe products during scheduled upgrades to contain costs.

“To strengthen collective resilience and safeguard confidential data, supply chains, and critical systems, public and private organizations must jointly act now,” the group wrote. “The transition to PQC is the key foundation to help build a secure and resilient digital future.”