DatingDapp
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Submission Details
Severity: low
Invalid

Fee Withdrawal Vulnerability Leads to Permanent Fund Locking

teoslaf

Summary

If the withdrawFees transaction fails, the contract updates totalFees to 0 before verifying a successful transfer, leading to a scenario where fees are permanently locked in the contract.

Vulnerability Details

The withdrawFees function first sets totalFees = 0 before attempting to transfer the funds. If the transfer fails (e.g., due to a malicious recipient rejecting ETH transfers), the contract still updates totalFees, making it impossible to withdraw the locked funds in future attempts.

Impact

  • Funds are permanently locked inside the contract.

  • Owners cannot recover fees, leading to potential financial losses.

  • Denial of Service (DoS) risk if an attacker exploits this to prevent withdrawals.

Tools Used

Manual review

Recommendations

Update totalFees only after a successful transfer:

function withdrawFees() external onlyOwner {
require(totalFees > 0, "No fees to withdraw");
uint256 totalFeesToWithdraw = totalFees;
​
(bool success, ) = payable(owner()).call{value: totalFeesToWithdraw}("");
require(success, "Transfer failed");
​
totalFees = 0; // Update state only after success
}
Updates

Appeal created

n0kto Lead Judge 6 months ago
Submission Judgement Published
Invalidated
Reason: Non-acceptable severity
Assigned finding tags:

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Please read the CodeHawks documentation to know which submissions are valid. If you disagree, provide a coded PoC and explain the real likelyhood and the detailed impact on the mainnet without any supposition (if, it could, etc) to prove your point.

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