function raiseDispute(bytes calldata _data, bytes calldata _signature)
    external
    override
{
    // Recover the signer from the signature
    address signer = SignatureDecoder.recoverKey(
        keccak256(_data),
        _signature,
        0
    );

    ...
  }
function recoverKey(
  bytes32 messageHash,
  bytes memory messageSignatures,
  uint256 pos
) internal pure returns (address) {
  if (messageSignatures.length % 65 != 0) {
      return (address(0));
  }

  ...
}
function raiseDispute(bytes calldata _data, bytes calldata _signature)
    external
    override
{
    // Recover the signer from the signature
    address signer = SignatureDecoder.recoverKey(
        keccak256(_data),
        _signature,
        0
    );

    // Decode params from _data
    (address _project, uint256 _task, , , ) = abi.decode(
        _data,
        (address, uint256, uint8, bytes, bytes)
    );

    // Revert if decoded project address does not match this contract. Indicating incorrect _data.
    require(_project == address(this), "Project::!projectAddress");

    if (_task == 0) {
        // Revet if sender is not builder or contractor
        require(
            signer == builder || signer == contractor, // @audit-info if `contractor = address(0)` and the recovered signer is also the zero-address, this check will pass
            "Project::!(GC||Builder)"
        );
    } else {
        // Revet if sender is not builder, contractor or task's subcontractor
        require(
            signer == builder ||
                signer == contractor || // @audit-info if `contractor = address(0)` and the recovered signer is also the zero-address, this check will pass
                signer == tasks[_task].subcontractor,
            "Project::!(GC||Builder||SC)"
        );

        if (signer == tasks[_task].subcontractor) {
            // If sender is task's subcontractor, revert if invitation is not accepted.
            require(getAlerts(_task)[2], "Project::!SCConfirmed");
        }
    }

    // Make a call to Disputes contract raiseDisputes.
    IDisputes(disputes).raiseDispute(_data, _signature); // @audit-info Dispute will be created. Anyone can spam the system with fake disputes
}
function raiseDispute(bytes calldata _data, bytes calldata _signature)
    external
    override
{
    // Recover the signer from the signature
    address signer = SignatureDecoder.recoverKey(
        keccak256(_data),
        _signature,
        0
    );

    require(signer != address(0), "Zero-address"); // @audit-info Revert if signer is zero-address

    ...
  }
