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Submission Details
Severity: low
Invalid

usage of transfer instead of call

dinkras

Summary

Vulnerability Details

Even though the issue was reported by LightChaser it was partially reported, so this report is going to enhance it. The issue originates from the fact that using transfer() is not reccomended anymore due to it's low gas usage restriction. As a result a big number of the modern smart contract txs will fail. Their fallback(), receive() just take more gas.

An instance of the issue is reported by LightChaser inTokenManager.withdraw(), however it was not discovered in Rescuable.rescue(). This is with way bigger impact than withdraw because a big number of the protocol contracts inhering Rescuable.

function rescue(
address to,
address token,
uint256 amount
) external onlyOwner {
if (token == address(0x0)) {// ETH
payable(to).transfer(amount);// @audit-issue found by LightChaser, however report it with enhancements: use call instead of transfer. More details in vuln folder: title: usage of addr.transfer() instead of call()
} else {// Tokens
_safe_transfer(token, to, amount);
}
​
emit Rescue(to, token, amount);
}

Another thing that was missed from the LightChaser report is that the withdraw proccess is more complex. In some instances users need to settle their ask/bid offers first, and only after that they are able to withdraw the deposited funds.

Impact

Users using smart contracts whose fallback or receive functions take > 2300 gas cannot receive their WETH, nor the protocol can rescue funds to some addresses whose fallback(),receive() require more than that amount of gas.

Tools Used

Recommendations

Use call{}(), instead of transfer() when transfering ETH

Updates

Lead Judging Commences

0xnevi Lead Judge 10 months ago
Submission Judgement Published
Invalidated
Reason: Known issue
Assigned finding tags:

[invalid] finding-TokenManager-withdraw-transfer-2300-gas

Invalid, known issues [Medium-2](https://github.com/Cyfrin/2024-08-tadle/issues/1)

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