ecrecover zero-address return unchecked

Usual (USD0 / bUSD0 / USUAL)'s assessment for RD-F-019 — scored green on the v1.7.0 rubric. The evidence below is the curator's reasoning for this score.

Evidence summary #

USD0 uses ERC20PermitUpgradeable (OZ standard with proper ecrecover guards). DaoCollateral uses NoncesUpgradeable for replay protection. OZ standard implementations include address(0) guard. No auditor-reported finding on this class.

Sources #

Etherscan
USD0 Implementation — EtherscanUSD0 impl — ERC20PermitUpgradeable includes ecrecover guardretrieved 2026-05-17
Etherscan
DaoCollateral Implementation — EtherscanDaoCollateral impl — NoncesUpgradeableretrieved 2026-05-17

Methodology #

Determine whether any `ecrecover` call result is used without a `!= address(0)` guard.

See the full factor methodology and distribution across all protocols →

rubric_version v1.7.0 protocol usual factor RD-F-019 score green collected_at 2026-05-16 20:39:44