Escher contest - shark's results

Lines of code

https://github.com/code-423n4/2022-12-escher/blob/main/src/minters/LPDA.sol#L105

Vulnerability details

Impact

In LPDA.sol, using transfer() may cause ETH to be un-retrievable if the msg.sender is a smart contract. ETH can potentially be lost if:

• the contract does not implement a payable fallback function
• the fallback function uses more than 2300 gas units

Proof of Concept

File: LPDA.sol Line 105

        payable(msg.sender).transfer(owed);

Recommended Mitigation Steps

Use call() with a success check instead of transfer().

For example:

(bool success, ) = payable(msg.sender).call{ value: owed }('');
require(success, "Transfer failed");