Researchers pitch quantum fix that keeps existing Bitcoin addresses

Wyoming-based blockchain security firm @Americanfort_io has proposed a cryptographic scheme it says could make $BTC wallets resistant to quantum attacks without requiring users to move funds or change their addresses, a step that has stalled most existing proposals.

How ZKPoSP Works

Researchers at AmericanFortress have proposed a system they say could allow Bitcoin and other blockchain wallets to withstand future quantum attacks without changing existing wallet addresses. In a paper titled "ZKPoSP: Post-Quantum Zero-Knowledge Proofs for Hierarchical Deterministic Wallets," the team describes replacing traditional elliptic curve signatures with zero-knowledge proofs while maintaining compatibility with hierarchical deterministic wallets.

The proposal, named ZKPoSP for Zero-Knowledge Proof of Seed Provenance, drops the signing step and has the wallet prove it knows the seed instead, using zero-knowledge proofs. The wallet demonstrates it knows the seed behind the address without ever exposing the seed. Nodes check the proof and clear the transaction. The address stays exactly the same.

The approach remains a proposal and would require node-level upgrades before any blockchain could enforce it. Its post-quantum security remains conjectural, according to the technical paper, rather than proven against a working attack. AmericanFortress released the paper through the International Association for Cryptologic Research's ePrint archive.

The system was implemented in Rust using the RISC Zero zero-knowledge virtual machine. Prototype benchmarks showed proof generation times of roughly 12 to 13 seconds and verification times of about 9 to 10 milliseconds.

The Scale of the Problem

Glassnode analysis found that 6.04 million $BTC, or 30.2% of the issued supply, is exposed to quantum risk, while the remaining 13.99 million BTC shows no public-key exposure. The quantum concern is that a sufficiently capable quantum computer, using an algorithm known as Shor's algorithm, could in principle recover a private key from a known public key.

Structurally exposed coins sit in script formats that reveal the public key by design, including early pay-to-public-key outputs associated with Bitcoin's pseudonymous founder Satoshi Nakamoto, legacy multisignature structures, and more recent Taproot outputs. Many of these coins may be effectively immovable, lost wallets or dormant holdings that cannot be voluntarily migrated to safer address formats.

The research has not been adopted by any blockchain network. Any deployment would require adoption by developers, wallet providers, exchanges, miners, and users. The real challenge was never purely technical. Agreeing on a single path forward across a decentralized ecosystem is proving to be the harder problem.

Sources:
Decrypt: There's a New Way to Protect Bitcoin From Future Quantum Attacks, Researchers Say
Decrypt: Nearly $500B in Bitcoin Is Exposed to Future Quantum Computing Attacks, Glassnode
Crypto.news: AmericanFortress Proposes Quantum-Safe Crypto Wallet Scheme