User Registration Failure When useRegistryAnchor is Enabled

The RFPSimpleStrategy contract exhibits a critical flaw in user registration when the useRegistryAnchor flag is set to true, making it impossible for users to register as recipients.

Vulnerability Detail

In RFPSimpleStrategy contract, when a user register as a recipient, it call the function _registerRecipient.

https://github.com/sherlock-audit/2023-09-Gitcoin/blob/main/allo-v2/contracts/strategies/rfp-simple/RFPSimpleStrategy.sol#L314-L380

Within the _registerRecipient function in the RFPSimpleStrategy contract, a conditional statement exists to evaluate whether the useRegistryAnchor flag is active.

            if (useRegistryAnchor) {        
                    /// @custom:data when 'true' -> (address recipientId, uint256 proposalBid, Metadata metadata)
                    (recipientId, proposalBid, metadata) = abi.decode(_data, (address, uint256, Metadata));

                    // If the sender is not a profile member this will revert
                    if (!_isProfileMember(recipientId, _sender)) revert UNAUTHORIZED();

https://github.com/sherlock-audit/2023-09-Gitcoin/blob/main/allo-v2/contracts/strategies/rfp-simple/RFPSimpleStrategy.sol#L327-L332

The function neglects to assign a value to recipientAddress. This omission leads to a later part of the function which checks for a zero address and reverts the transaction if found.

            // If the recipient address is the zero address this will revert
            if (recipientAddress == address(0)) revert RECIPIENT_ERROR(recipientId);

https://github.com/sherlock-audit/2023-09-Gitcoin/blob/main/allo-v2/contracts/strategies/rfp-simple/RFPSimpleStrategy.sol#L362

Impact

This flaw disrupts the fundamental utility of the contract. It prevents users from successfully registering as recipients when the useRegistryAnchor flag is active, effectively breaking this feature.

Code Snippet

https://github.com/sherlock-audit/2023-09-Gitcoin/blob/main/allo-v2/contracts/strategies/rfp-simple/RFPSimpleStrategy.sol#L327-L332 https://github.com/sherlock-audit/2023-09-Gitcoin/blob/main/allo-v2/contracts/strategies/rfp-simple/RFPSimpleStrategy.sol#L362

Tool used

Manual Review

Recommendation

Assign the recipientAddress to the address of recipientId or another address.

Duplicate of #245

sherlock-audit / 2023-09-Gitcoin-judging