Submitted by inh3l, also found by 0xLasadie, aua_oo7, bareli, bumbleb33, Daniel526, Daniel526, eta, Evo, gajiknownnothing, inh3l, Ryonen, Le_Rems, m4k2, mansa11, MrMatrix, phenom80, saikumar279, Shubham, and Vagabond
https://github.com/code-423n4/2024-12-lambowin/blob/874fafc7b27042c59bdd765073f5e412a3b79192/src/LamboVEthRouter.sol#L179-L183
https://github.com/code-423n4/2024-12-lambowin/blob/874fafc7b27042c59bdd765073f5e412a3b79192/src/LamboVEthRouter.sol#L188
Over time, ETH will be accumulated in the LamboVEthRouter and it will be irretrievable leading to loss of funds.
First, LamboVEthRouter.sol has a receive function that allows users to send ETH to the contract.
Also, in the _buyQuote function, there is a check for if the msg.value is greater than the amountXIn + fee + 1. If it is, it will refund the user the excess ETH minus 1 wei.
Over time, with the amount of transactions that will be processed, the accumulated 1 weis including any other excess ETH will all add up to a significant amount. Also, as ETH price increases, these small costs can eventually become quite substantial. But theres no way to sweep the tokens out of the contract. Hence loss of funds for both users and the protocol.
Include a sweep function in the contract, or refund actual excess amount to the users.
Shaneson (Lambo.win) acknowledged
