What changed with EIP-7702?

EIP-7702, live on Ethereum since the Pectra upgrade in May 2025, lets an ordinary externally owned account delegate to contract code. Contracts that assumed msg.sender == tx.origin means 'no contract code' can no longer rely on that, and the delegated code becomes part of the wallet's security.

Do you test wallet apps as well as contracts?

Yes. The audit covers the contracts. Signing flows, key storage and the app itself are covered by our wallet penetration testing.

Smart Wallet and Account Abstraction Audit

Smart wallet and account abstraction audits

Smart wallets hold user funds directly, so their validation logic is the security boundary. HYDN audits ERC-4337 accounts, paymasters and modules, multisig and recovery schemes, ERC-1271 signature validation, and wallets that use EIP-7702 delegation, looking for any way to authorise a transaction the owner did not sign.

ERC-4337 accounts

validateUserOp must reject anything not authorised by the owner, and must not have side effects an attacker can exploit during validation.
Nonces and replay protection across chains.
Paymasters: who they sponsor, how they are repaid, and whether an attacker can drain their deposit.
Interaction with the EntryPoint and bundlers, including gas griefing.

Modules and plugins

Modular wallets let third-party code act on the account. We check how modules are installed, what they are allowed to call, and whether one module can be used to install another or remove the owner.

Signatures

ERC-1271 implementations that other protocols trust to validate signatures on the wallet’s behalf.
Signatures bound to chain ID, contract address and nonce. See signature replay.
Malleability and the handling of invalid or zero signatures.

Recovery

Social recovery and guardian schemes are a second way to take control of the wallet. We check thresholds, delays, how guardians are changed, and whether recovery can be triggered against the owner’s wishes.

EIP-7702 delegation

When an EOA delegates to contract code, that code runs with the account’s full balance. We review delegate contracts for initialisation and storage issues, and check integrations for assumptions that an EOA has no code.