Ethereum developers propose upgrading the staking contract to defend against quantum attacks

According to CoinDesk, Ethereum researchers have proposed rebuilding the validator deposit contract to support a new cryptographic system and ultimately stop accepting deposits protected by the existing BLS signatures. This proposal targets the deposit contract, aiming to add a switch that prevents the network from accepting the currently relied-upon signature format.

Currently, the contract only accepts BLS keys because their exact size is hardcoded, while the new draft allows for different key sizes, with each deposit tagged by the cryptographic system used, where BLS receives a tag of zero, reserving space for future schemes.

If the proposal is approved, it will initially operate with BLS deposits, while other schemes can be registered simultaneously. Future decisions may permanently disable new BLS deposits, at which point validators who have staked using BLS keys will not disappear, but new validators will not be able to join using this method. Ethereum will ultimately need to change separately to inform validators how to check new signatures. This is part of the migration for validators, while another part is already in progress—EIP-8141 framework transaction proposals will allow regular Ethereum accounts to change the cryptographic method for approving transactions without changing their address.

The urgency stems from research released in March by Google's Quantum AI research department, which outlined five quantum attack paths against Ethereum, putting over $100 billion in assets at potential risk. The Ethereum Foundation is advancing core protocol changes with a target around 2029. Currently, the amount of ETH staked in Ethereum is approximately 42.4 million, valued at about $10.4 billion.