Bitcoin Developers Sound Alarm on Quantum Threat, Propose Fix for Legacy Addresses

• Quantum computing is considered an “existential threat” to cryptographic systems.
• A new proposal seeks to phase out vulnerable legacy BTC wallet addresses.
• Quantum computers may become powerful enough to launch a 51% attack on the Bitcoin network successfully.

Bitcoin (BTC) developers are sounding the alarm on quantum computing, warning it could break the network’s encryption within the next decade.

In response, they’re proposing to gradually phase out legacy addresses, including those linked to Satoshi Nakamoto, in a bid to safeguard nearly 25% of Bitcoin’s total supply from potential quantum threats.

A Bitcoin Threat

According to a proposal from Jameson Lopp, CTO and co-founder of self-custody platform Casa, advances in quantum computing represent a growing threat to the integrity and security of the Bitcoin network.

The proposal writes:

“Never before has Bitcoin faced an existential threat to its cryptographic primitives. A successful quantum attack on Bitcoin would result in significant economic disruption and damage across the entire ecosystem.”

Bitcoin’s code relies on elliptic curve cryptography, which quantum computers could exploit using algorithms to derive public keys from private ones.

This would leave legacy address types such as pay-to-public-key (P2PK) and reused pay-to-public-key-hash addresses, potentially exposing roughly 25% of the total supply of BTC to theft.

This could result in huge losses across the market, also compromising miners and network security.

Phased Out

Lopp’s Bitcoin Improvement Proposal (BIP), co-authored by five other devs, suggests phasing out the aforementioned risky, legacy addresses over a five-year period.

More specifically, it would prevent token transfers to vulnerable addresses and also prevent them from making transactions after a certain date and time.

This would freeze them, rendering them unusable if owners fail to migrate to quantum-resistant alternatives such as SLH-DSA or post-quantum cryptography schemes.

A third optional phase, which is pending further research, could see the creation of a new BIP and introduce a quantum-safe method to recover frozen BTC from legacy addresses.