Banks Must Prepare for Ethereum Quantum Upgrade by 2027

Thomas Brunner, head of custody and staking at Sygnum Bank, warns that banks must start preparing for Ethereum's planned quantum-resistant upgrade by 2027. This is because the transition to new cryptographic methods will require strict controls, including a ban on reusing keys.

This creates a conflict with current banking practices, where systems are often duplicated or rolled back during backup and disaster recovery processes.

Brunner estimates that identifying a bank's cryptographic keys and related systems alone can take six months to a year.