Latest “quantum computer breaks the math behind Bitcoin” headlines massively exaggerate risk

A recent demonstration where a researcher used publicly accessible quantum hardware to derive a 15-bit elliptic curve private key from its public key has been highlighted. While this is the largest public demonstration to date of an attack class that could one day threaten systems secured by elliptic curve cryptography, it is crucial to understand that a 15-bit key is vastly less secure than Bitcoin's 256-bit elliptic curve. No publicly known quantum computer can break real Bitcoin wallets today. The demonstration used a variant of Shor's algorithm, targeting the elliptic-curve discrete logarithm problem, which is the mathematical foundation of Bitcoin's signature scheme. However, the competition rules required breaking the largest possible ECC key without classical shortcuts, and the winning machine had only about 70 qubits. The real significance of this event lies in the accelerating progress in quantum computing, with Google recently reducing its resource estimates for breaking ECC keys and setting a 2029 migration deadline for post-quantum cryptography. This, along with similar moves by Cloudflare and research suggesting faster quantum architectures, indicates that the timeline for a quantum threat to cryptocurrencies is becoming more concrete, even if the immediate risk is exaggerated by headlines. The article emphasizes that while the threat is still in the future, the ecosystem needs to prepare for migration, with potential scenarios ranging from routine upgrades to a race against time if technical progress outpaces governance and coordination.

(Source：CryptoSlate)