EU supervisors warn quantum computers could break crypto security

European Union financial supervisors issued a warning on Wednesday, stating that advancements in quantum computing pose a potential threat to the cryptography that secures blockchains. The joint risk update from the European Banking Authority, European Insurance and Occupational Pensions Authority, and European Securities and Markets Authority highlighted that quantum computing could compromise systems used for transactions, communications, and databases. This concern is amplified by recent assessments from Google Quantum AI, whose researchers in March estimated that breaking the cryptography used by many cryptocurrencies might require significantly fewer physical qubits than previously projected. A qubit is the fundamental unit of a quantum computer, and while no computer capable of such an attack currently exists, the potential for future development is a significant worry. For cryptocurrency holders, the primary concern is that a powerful quantum computer could potentially derive a private key from an exposed public key, thereby enabling unauthorized transaction authorization. In response to these potential threats, Bitcoin developer Jameson Lopp, along with five other developers, proposed a plan in February to gradually phase out the network's current signature methods and restrict the spending of unmigrated funds five years after the proposal's activation, though this proposal has not yet been adopted. Meanwhile, the Ethereum Foundation has set a target to achieve quantum resistance across Ethereum's execution, consensus, and data layers by December 2029.