Citi: Quantum computing breakthroughs are accelerating, Bitcoin faces significant quantum risks

ChainCatcher news, Citibank stated in its latest report that quantum computing technology is advancing faster than the market expects, rapidly accelerating the potential security risks faced by cryptocurrencies and internet infrastructure, with Bitcoin considered one of the assets with the greatest risk exposure. The report notes that the ECDSA elliptic curve encryption system currently used by Bitcoin could, in theory, be broken by a sufficiently powerful quantum computer. In the future, attackers may be able to derive private keys from publicly available public keys, enabling them to forge transactions and steal assets.

Citi analyst Alex Saunders explained that, due to Bitcoin’s relatively conservative governance mechanism and slow protocol upgrade speed, it is more difficult for Bitcoin to quickly complete a quantum-resistant upgrade compared to PoS networks like Ethereum. The report estimates that around 6.5 million to 6.9 million BTC face potential quantum risks because their public keys have been exposed, accounting for about one-third of the current circulating supply and valued at roughly $450 billion at present prices. This includes some early P2PK addresses and wallets believed to belong to Satoshi Nakamoto.

Citi also warns of the “Harvest Now, Decrypt Later” risk, meaning attackers may collect encrypted data now and decrypt it once quantum computing power matures in the future. However, Citi remains optimistic about the long-term adaptability of the crypto industry, believing that blockchains can still migrate through post-quantum cryptography and protocol restructuring. The report mentions that upgrade proposals BIP-360 and BIP-361, currently being discussed by the Bitcoin community, warrant attention.