Blockchain security company AmericanFortress has unveiled a cryptographic scheme that it says could protect existing cryptocurrency wallets from future quantum attacks without requiring users to move funds, rotate keys or change wallet addresses.
Unlike most proposed post-quantum approaches, AmericanFortress said its scheme allows existing wallet addresses to remain unchanged while adding post-quantum protection.
The company published the proposal in a technical paper on the Cryptography ePrint Archive, describing the scheme as compatible with seed-based hierarchical deterministic wallets used across Bitcoin (BTC), Ethereum (ETH), Solana (SOL) and other blockchain networks that rely on elliptic curve cryptography. The paper has not yet been peer-reviewed.
According to the paper, the scheme uses zero-knowledge proofs derived from a wallet’s original seed phrase instead of replacing the elliptic curve cryptography underlying existing wallets. AmericanFortress said participating nodes would verify those proofs while users continue signing transactions with their existing keys.
AmericanFortress also cited a recent Bloomberg analysis estimating that up to $470 billion in Bitcoin could be vulnerable to quantum attacks if sufficiently powerful quantum computers become available.
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Companies pursue different paths to post-quantum wallet security
AmericanFortress is not the only company developing post-quantum protections for cryptocurrency wallets. On Tuesday, Freedom Factory unveiled PQ1, which it describes as a post-quantum hardware wallet designed for Ethereum and other Ethereum Virtual Machine (EVM)-compatible networks.
Unlike AmericanFortress’ software-based approach, PQ1 uses post-quantum cryptographic signatures generated on dedicated hardware. According to Freedom Factory, the wallet uses SPHINCS+C10 signatures and ERC-4337 smart accounts to secure transactions against future quantum attacks.
Developers have increasingly focused on post-quantum cryptography because sufficiently powerful quantum computers could eventually break the elliptic-curve cryptography used to secure Bitcoin, Ethereum and many other blockchain networks. Although such computers are not yet available, several blockchain projects have already begun researching migration strategies.
In recent months, a Strategy-led consortium pledged $15 million to fund Bitcoin quantum security research, the Ethereum Foundation published a proposal for migrating accounts to quantum-resistant cryptography, and Algorand outlined plans to introduce quantum-resistant accounts by 2027.
Ethereum’s post-quantum roadmap. Source: Ethereum Foundation
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