Bitcoin's Quantum Computing Risk: A Growing Threat

A recent technical report by Presidio Bitcoin has shed light on the growing threat of quantum computing to the Bitcoin network. In the report, the non-profit group examines the current state of quantum capabilities and their potential impact on Bitcoin's cryptographic security.

Presidio notes that Bitcoin is a software-based system, which both enables its flexibility and exposes it to digital risks. One of the key risks identified is the threat posed by cryptographically relevant quantum computers (CRQCs), which could potentially break the elliptic curve cryptography used in Bitcoin by deriving private keys from public keys.

The report estimates that if a CRQC were to exist today, approximately 6.5 million BTC - one-third of the total supply - would be immediately vulnerable to theft. This estimate is broken down into three categories: address reuse (4.5 million BTC), legacy pay-to-pubkey (P2PK) outputs (1.72 million BTC), and addresses that have never been spent.

Presidio also highlights the uncertainty surrounding the timeline for CRQCs, with expert surveys placing the probability of their emergence between 2030 and 2035 at around 50%. In response to this threat, the report recommends deploying post-quantum signature schemes via a soft fork to mitigate the risk of quantum-enabled theft.