Unchecked Return Value

Summary

OpenZeppelin Contracts is a library for smart contract development. Versions 4.0.0-beta.0 through 4.7.0 are vulnerable to ERC165Checker reverting instead of returning `false`. `ERC165Checker.supportsInterface` is designed to always successfully return a boolean, and under no circumstance 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-165 as expected, specifically if it returns a value other than 0 or 1. The contracts that may be affected are those that use `ERC165Checker` to check for support for an interface and then handle the lack of support in a way other than reverting. The issue was patched in version 4.7.1.