TLDR
- Ethereum researchers proposed rebuilding the validator deposit contract to support quantum-resistant cryptography
- Around 42.4 million ETH, worth roughly $104 billion, is currently at risk from future quantum attacks
- The current BLS signature format is vulnerable to quantum computers running Shor’s algorithm
- The urgency stems from a Google Quantum AI report that mapped five quantum attack paths against Ethereum
- The Ethereum Foundation is targeting 2029 for core protocol security changes
Ethereum developers have put forward a proposal to overhaul the network’s validator deposit contract to protect the blockchain from future quantum computer attacks.
LATEST: 🔒 Ethereum devs propose rebuilding the validator deposit contract to allow future quantum-resistant signature types before eventually phasing out today's BLS format, an early step to shield ETH staking from quantum attacks. pic.twitter.com/vJZCpxXdYv
— CoinMarketCap (@CoinMarketCap) August 27, 2026
The proposal targets the deposit contract, the entry point where users lock up Ether to become validators. Validators are the operators who verify transactions and keep the blockchain running.
Roughly 42.4 million ETH is currently staked on the network. At current prices, that amounts to around $104 billion, all of it secured by the signature format developers now want to replace.
The Problem With Current Signatures
Ethereum validators currently sign transactions using a system called BLS signatures. The main advantage of BLS is that hundreds of thousands of signatures can be compressed into one, keeping the network’s consensus process affordable.
The problem is that BLS is built on elliptic curve mathematics. A powerful enough quantum computer running Shor’s algorithm could break that math, allowing an attacker to forge a validator’s signature.
The existing deposit contract hard-codes the size of BLS keys, meaning Ethereum cannot accept a quantum-resistant signature in its current form, even if developers agreed on one today.
The new proposal would change that by allowing different key sizes, with each deposit tagged to show which cryptographic system it uses. BLS would remain operational initially, but a later decision could permanently stop new BLS deposits from being accepted.
Validators already staking with BLS keys would not be removed, but new validators would be unable to join using the old format.
Google’s Research Sparked Action
The push to act on quantum security traces back to a Google Quantum AI research report published earlier this year.
The report mapped five quantum attack paths against Ethereum and identified more than $100 billion in assets at potential risk, spanning wallets, staking, smart contracts and layer-2 systems.
The proposal also retires the old deposit-processing system Ethereum has used since staking launched in 2022, shifting deposits onto a newer framework already handling withdrawals and validator changes.
This is one half of a broader migration. The other half is already in motion through a separate proposal under consideration for the Hegotá upgrade, due later this year. That proposal would allow ordinary Ethereum accounts to update their cryptographic security without moving to a new address.
The current proposal is an early draft awaiting review and has been suggested for the number EIP-8394.
The Ethereum Foundation is targeting around 2029 for the core protocol changes needed to fully address the quantum threat.
Ether was trading at around $2,475 on August 26.
