Ledger CTO Warns Quantum Computing Could Expose Bitcoin and Crypto Elliptic Curve Keys

Ledger CTO Charles Guillemet said quantum computers powerful enough to break Elliptic Curve Cryptography could allow attackers to derive private keys from exposed public keys across major blockchains. He noted that Bitcoin public keys are revealed when coins are spent and were directly embedded in early pay-to-public-key outputs, leaving about 7 million BTC, including roughly 1 million attributed to Satoshi Nakamoto, theoretically vulnerable in an advanced quantum scenario. Guillemet said hardware signers are now the preferred way to secure cryptocurrencies because keys remain offline and signatures are generated inside a Secure Element, and Ledger is running post-quantum cryptography experiments in Secure Elements using software-only implementations despite significant RAM and compute constraints. He added that post-quantum cryptography offers quantum-resistant signature schemes in hash-based and lattice-based families, but stressed that secure implementation in signers is complex, while Ethereum cofounder Vitalik Buterin has separately outlined a roadmap to protect the Ethereum network from future quantum threats.