- SEC reviews 74-page proposal addressing quantum risks, urging immediate audits, wallet protections, and migration to post-quantum encryption.
- Experts warn “Q-Day” could arrive by 2028, threatening Bitcoin, Ethereum, and trillions in crypto assets relying on elliptic cryptography.
The U.S. Securities and Exchange Commission is reviewing a proposal to prepare crypto networks for quantum attacks. The plan targets Bitcoin, Ethereum, and other assets that rely on public-key cryptography.
Experts warn that “Q-Day,” when quantum machines can break today’s encryption, could arrive by 2028. Trillions in digital value would face direct theft risk if keys become computable.
The 74-page Post-Quantum Financial Infrastructure Framework, filed by Daniel Bruno Corvelo Costa, outlines immediate steps and a staged migration. It calls for exchange and custodian audits, triage of high-risk wallets, and adoption of post-quantum schemes that align with standards finalized by NIST. Moreover, the paper flags “Harvest Now, Decrypt Later” tactics, where attackers store encrypted data today to unlock it once hardware improves.
Bitcoin’s design presents a clear attack path. Elliptic curve signatures (ECDSA) could be solved by a capable quantum computer, exposing dormant balances, including early wallets attributed to Satoshi Nakamoto.
BlackRock’s iShares Bitcoin Trust listed quantum risk in regulatory filings this year, reinforcing the need for planning. In July, developers floated time-bound restrictions on older address types to reduce exposure within five years. However, any rule that freezes coins would require broad consent and careful execution.
Regulatory context also matters. U.S. officials are studying a national crypto reserve, which would demand resilient key management. Meanwhile, market maker Wintermute asked the SEC to clarify that network tokens used for protocol operations are not securities, arguing they resemble commodities. Misclassification could shift activity offshore and weaken domestic oversight.
Bitcoin and the Quantum Threat: A Mathematical Outlook
The security of Bitcoin rests on elliptic curve cryptography, specifically the Elliptic Curve Digital Signature Algorithm (ECDSA) over the curve secp256k1. Private keys are 256-bit numbers, yielding about 1.16 × 10⁷⁷ possible values. A classical computer, even running at 10³⁰ guesses per second, would never exhaust this search space within the age of the universe.
The concern lies with quantum computing. Shor’s algorithm allows discrete logarithm problems, which underpin ECDSA, to be solved in polynomial time instead of exponential. The difference is profound: a problem once practically unsolvable could, in theory, become accessible. Estimates suggest that breaking a 256-bit key with Shor’s method would require roughly 2,330 logical qubits and up to 10¹² quantum gate operations. With error correction included, the demand scales to 10⁷–10⁸ physical qubits.
Current quantum computers have around 1,000 physical qubits in 2025, far below what is required. Closing that gap means advancing hardware by five orders of magnitude. Academic projections range from late 2030s feasibility under steady progress, to more aggressive models that place the risk window between 2028 and 2035. The uncertainty reflects how little is known about scaling qubit stability and correcting errors at industrial levels.
Mathematically, the probability of Bitcoin being broken today is close to zero. Formally, if P denotes the probability of a successful quantum break within t years, then P is a function of the available logical qubits Q(t) and resources R for gate operations. With Q(2025) much less than 2,330, P is negligible. However, as Q(t) approaches the 10⁷–10⁸ physical threshold, P approaches certainty.
