Submission Details
Severity:
Potential denial of Service by withdrawing funds, on `address.transfer (2300 gasLimit)`.
Summary
Usage of address.transfer built-in method might revert if Owner is a contract containing heavy operations on receive or fallback since transfer only supports a max gas usage of gasLimit = 2300 . producing DOS which locks the funds of SpookySwap forever.
Vulnerability Details
built-in transfer function not recommended.
function withdrawFees() public onlyOwner {
uint256 balance = address(this).balance;
@> payable(owner()).transfer(balance);
emit FeeWithdrawn(owner(), balance);
}
Impact
Protocol's Funds stay locked unless recipient handles receive ether under less than 2300 gas. SpookySwap:changeOwner mechanism doesn’t directly mitigate the risk of funds being inaccessible.
Tools Used
Manual Review
Foundry testing tool
contract Owner {
uint256 val;
receive() external payable {
uint256 gas = gasleft();
uint256 consumed;
//100
while (consumed <= 2300) {
val = type(uint256).max;
consumed += gas - gasleft();
gas = gasleft();
}
}
}
function testDOSonWithdrawFees() public {
Owner owner = new Owner();
SpookySwap.Treat memory treat = SpookySwap.Treat("candy", 0.1 ether, "ipfs://candy-cid");
SpookySwap.Treat[] memory treats = new SpookySwap.Treat[]();
treats[0] = treat;
vm.prank(address(owner));
SpookySwap _protocol = new SpookySwap(treats);
vm.prank(user);
_protocol.trickOrTreat{ value: 0.2 ether }("candy");
vm.prank(address(owner));
vm.expectRevert();
_protocol.withdrawFees();
}
Recommendations
use low level
address.callinstead
Updates
Appeal created
bube about 1 year ago
Submission Judgement Published Assigned finding tags:
Use of `transfer` instead of `call`
Rewards breakdown
nSLOC
109This contest has a flat reward structure with the following payouts:
100 EXP
20 EXP
2 EXP
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