An analysis has raised the prospect that Ethereum (ETH) and Solana (SOL) are exposed to significant security threats in a future era of quantum computers.

On May 7, blockchain outlet BeInCrypto reported that quantum security research group Project Eleven, in its latest report, assessed that about 65 percent of Ethereum and virtually all of Solana’s network, or 100 percent, are vulnerable to quantum attacks.

The report’s core point is that the public-key cryptography used by major blockchains today could be rendered ineffective in a quantum-computing environment. Quantum computers have the potential to quickly decrypt codes that are effectively difficult to break with conventional computers. Concerns have persisted that once sufficiently powerful quantum computers emerge, many current blockchain wallets and verification systems could be put at risk.

Ethereum uses the Elliptic Curve Digital Signature Algorithm (ECDSA) for account security and applies BLS signatures to its proof-of-stake (PoS) consensus structure. It uses KZG commitments for the blob data structure introduced through the EIP-4844 upgrade. Project Eleven analysed that all three could be exposed to quantum attacks.

It singled out validator key issues as one of the biggest risks. Ethereum validators expose their BLS public keys from the moment they stake 32 ETH, and if an attacker uses a quantum computer to reverse-engineer the key, it could generate false validation messages or disrupt the consensus process. The report warned that such a scenario could lead to large-scale slashing and network instability.

Solana was assessed as structurally more vulnerable. Solana uses an Ed25519-based structure, and each wallet address directly includes public-key information. Project Eleven explained that this means "all Solana addresses are essentially quantum-vulnerable." By contrast, it compared bitcoin as having a relative buffer because, under its UTXO structure, public keys for unused addresses may not be exposed in some cases.

The industry is preparing responses. The Ethereum Foundation (EF) in March released a 'Post-Quantum Ethereum' website and presented a roadmap for migration to quantum-resistant security. The foundation said it expects a layer-1 upgrade to be possible by 2029, but projected that migrating the entire execution layer could extend beyond that.

The Solana ecosystem is also preparing to adopt quantum-resistant cryptography. Validator client developers Anza and Firedancer each presented a direction to adopt the quantum-resistant signature method Falcon, approved by the U.S. National Institute of Standards and Technology (NIST). The Solana Foundation said it is proceeding with research and deployment preparation to a level that can be activated immediately if needed.

Project Eleven presented three scenarios for when the quantum threat could materialise. The optimistic case is 2030, the middle scenario is 2033 and the pessimistic case is 2042. It added that the outlook is based on the assumption of only gradual performance improvements each year and no major breakthrough.

In this environment, the actual speed and scope of migration to quantum-resistant security are emerging as key variables. Ethereum has multiple weak points across consensus and data structures, and Solana’s address system itself assumes public-key exposure. Both networks are preparing technical alternatives, but when protocol upgrades and execution-environment migration will be completed is expected to be a key point to watch in the security race ahead.