There’s a New Way to Protect Bitcoin From Future Quantum Attacks, Researchers Say

Researchers at AmericanFortress, a Wyoming-based blockchain security and cryptography company focused on post-quantum security and digital asset infrastructure, have proposed a cryptographic 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,” AmericanFortress researchers describe replacing traditional elliptic curve signatures with zero-knowledge proofs while maintaining compatibility with hierarchical deterministic wallets.

“Recent advances in quantum hardware, including Google’s Willow processor, have substantially narrowed the timeline to cryptographically relevant quantum computers,” they wrote. “In the blockchain setting, where addresses and key derivation standards such as BIP32, BIP44, and SLIP-10 are the dominant infrastructure for wallet management, a quantum computer running Shor’s algorithm can recover any elliptic-curve private key from the corresponding public key, threatening every wallet in production today.”

The research focuses on “Q-Day,” the point at which a fault-tolerant quantum computer could use Shor’s algorithm to derive private keys from public keys, rendering the elliptic curve cryptography used by Bitcoin and many other blockchains insecure.

Rather than requiring users to migrate funds to new quantum-safe addresses, the proposed system replaces digital signatures with zero-knowledge proofs that verify ownership of a wallet’s seed phrase. Because the seed itself remains secret, the authors argue legitimate owners could still prove control of their wallets even if individual private keys are compromised.

The paper introduces ZKPoSP (Zero-Knowledge Proof of Seed Provenance) and QBIP32, a key derivation scheme designed to support multiple elliptic curves while remaining compatible with existing hierarchical deterministic wallets.

According to the study, AmericanFortress researchers implemented the system 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 paper also describes a post-Q-Day mode that reduces proving time for some operations.

The research has not been adopted by any blockchain network. Any deployment would require adoption by developers, wallet providers, exchanges, miners, and users.

Interest in post-quantum cryptography has grown as blockchain developers prepare for Q-Day. Bitcoin presents a particular challenge because spending coins exposes their public keys on the blockchain. A sufficiently powerful quantum computer could use those public keys to derive private keys and forge valid transaction signatures.

The paper is the latest in a series of efforts across the crypto industry to prepare blockchain networks for a post-quantum future. Earlier this month, Project Eleven proposed a post-quantum recovery mechanism that would let users prove ownership of a Bitcoin wallet through its seed phrase rather than a digital signature after Q-Day.

In March, BTQ Technologies released the first working implementation of BIP-360 on a dedicated “Bitcoin Quantum” testnet to evaluate quantum-resistant transaction formats. In May, blockchain analytics firm Glassnode estimated that about 6.04 million Bitcoin, roughly 30% of the circulating supply, already have publicly exposed keys, while the U.S. Department of Commerce announced more than $2 billion in funding for quantum computing companies and manufacturing initiatives.

Last week, major companies including BlackRock, Coinbase, Strategy, Fidelity Digital Assets, Galaxy, and others formed the Bitcoin Security Consortium, committing $15 million over three years to support Bitcoin security research and defense against quantum attacks.