Quantum computers pose urgent threat to Bitcoin security

Experts warn the main quantum threat to Bitcoin is the interception and storage of encrypted authentication data, which could be decrypted once quantum computers advance.

Security experts and industry leaders are increasingly concerned about the quantum threat facing Bitcoin and the broader crypto ecosystem. Rather than focusing solely on quantum computers breaking wallet keys, experts highlight a more immediate risk: the interception and storage of encrypted authentication data and network traffic exchanged between institutions, exchanges, and custodians. This 'harvest now, decrypt later' strategy means adversaries are collecting encrypted messages, payment records, and authentication logs today, intending to decrypt them once quantum computers become powerful enough. Reports from Google, Citi, and blockchain security firms warn that millions of Bitcoin, particularly those with exposed public keys, could be vulnerable. While Ethereum has begun a post-quantum migration and Google targets a transition by 2029, Bitcoin and major exchanges have yet to implement similar protections. This leaves critical infrastructure and inter-institutional communications exposed to future quantum attacks.