The Standard

Summary

The fee tier of all uniswap pools vaults can interact with is hard-coded to 0.3%. Depending on the chain, token and user preference another fee tier might be more suitable, or the 0.3% fee tier might not even exist. Therefore, the fee tier should be manually passed as a parameter to the swap function.

Vulnerability Details

Here we can see the swap function and that it hard codes the fee tier for all chains and all collateral tokens:

Impact

All swaps are forced to use the same fee tier, which might not be the most suitable one, might not even exist or might be too high and therefore leads to a loss of user funds, as the user needs to pay more fees than needed.

Recommendations

The fee tier should be passed as a parameter to the swap function.