#43856 [SC-Low] Dispatcher._dispatch() does not revert on failure of transfer of funds when called with the TRANSFER_NATIVE command

Submitted on Apr 13th 2025 at 07:37:26 UTC by @Vanshika for Audit Comp | Spectra Finance

• Report ID: #43856

• Report Type: Smart Contract

• Report severity: Low

• Target: https://github.com/immunefi-team/Spectra-Audit-Competition/blob/main/src/router/Dispatcher.sol

• Impacts:

Description

Brief/Intro

Dispatcher._dispatch() silently fails if native ether transfer returns a false boolean.

Vulnerability Details

Dispatcher._dispatch() should revert if the following case returns a false value:

        function _dispatch(bytes1 _commandType, bytes calldata _inputs) internal {
            uint256 command = uint8(_commandType & Commands.COMMAND_TYPE_MASK);
            // function truncted to only show relevant parts.
            . . .
            else if (command == Commands.TRANSFER_NATIVE) {
            (address recipient, uint256 amount) = abi.decode(_inputs, (address, uint256));
            // call does not revert on failure
            (bool success, ) = payable(recipient).call{value: amount}("");
            }
            . . .
        }

In other if-clauses in the same function, a false boolean is reverted with a CallFailed() error as shown below. This is missing when command == TRANSFER_NATIVE.

    if (!success) {
        revert CallFailed();
    }

Impact Details

The function does not revert on failure, which may cause errors if there are other commands relying on its success.

Proof of Concept

Proof of Concept

Copy the following into RouterTest.t.sol and run with forge test --mt test_transferNativeRevert -vvvv.

    function test_transferNativeRevert() public {
        address alice = makeAddr("alice");
        bytes memory commands = abi.encodePacked(bytes1(uint8(Commands.TRANSFER_NATIVE)));
        bytes[] memory inputs = new bytes[](1);
        inputs[0] = abi.encode(alice, 1e18);
        
        vm.prank(testUser);
        router.execute(commands, inputs);

        // unsuccessful transfer but no revert
        assertEq(address(router).balance, 0);
        assertEq(alice.balance, 0);
    }

Expected result:

Suite result: ok. 1 passed; 0 failed; 0 skipped; finished in 7.23s (147.87ms CPU time)

Ran 1 test suite in 7.25s (7.23s CPU time): 1 tests passed, 0 failed, 0 skipped (1 total tests)