Beanstalk: The Finale

Summary

According to EIP-4494 specification: "The interface of this EIP (as defined in EIP-165) is 0x5604e225. Contracts implementing this EIP MUST have the supportsInterface function return true when called with 0x5604e225."

Vulnerability Details

The main functionality of TokenSupportFacet.sol contract is to permit ERC20 and ERC721 tokens and transfer of ERC721 and ERC1155, which should support EIP-4494, as it imports IERC4494.sol, the interface serves as an utilization for token permits for ERC721's, but there is no implemented support interface, which is against the specification.

Impact

Third-party protocols will not be able to check for token permits with the supportInterface function and the required interface id 0x5604e225.

Tools Used

Manual Review, EIP-4494 specification

Recommendations

Implement the recommendations of the EIP-4494 standard mentioned above.