title: OpenZeppelin Contracts's SignatureChecker may revert on invalid EIP-1271 signers
description: OpenZeppelin Contracts is a library for smart contract development. Versions 4.1.0 until 4.7.1 are vulnerable to the SignatureChecker reverting. `SignatureChecker.isValidSignatureNow` is not expected to revert. However, an incorrect assumption about Solidity 0.8's `abi.decode` allows some cases to revert, given a target contract that doesn't implement EIP-1271 as expected. The contracts that may be affected are those that use `SignatureChecker` to check the validity of a signature and handle invalid signatures in a way other than reverting. The issue was patched in version 4.7.1.
problem types: CWE-20: Improper Input Validation
affected:
{
product: openzeppelin-contracts
vendor: OpenZeppelin
versions:
status: affected, version: >= 4.1.0, < 4.7.1
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: NETWORK
availabilityImpact: NONE
baseScore: 7.5
baseSeverity: HIGH
confidentialityImpact: NONE
integrityImpact: HIGH
privilegesRequired: NONE
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
version: 3.1
]