TheNaubit - Rebalancer executes swaps without slippage protection

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TheNaubit

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Rebalancer executes swaps without slippage protection

Summary

The rebalancer contract calls USSD#UniV3SwapInput function that executes swaps without slippage protection. That will cause a loss of funds because of sandwich attacks.

Vulnerability Detail

The UniV3SwapInput function calls the Uniswap V3 function ExactInputParams to perform swaps (used to rebalance the protocol) but it is setting the param amountOutMinimum to 0, meaning there is no slippage protection in this swap.

Here is a similar report in the past: sherlock-audit/2023-01-derby-judging#64

Impact

Having set the amountOutMinimum param to 0 means there is no slippage protection in the swap. Therefore swaps will be sandwiched causing a loss of funds every time the protocol rebalances.

Code Snippet

https://github.com/sherlock-audit/2023-05-USSD/blob/main/ussd-contracts/contracts/USSD.sol#L237

Tool used

Manual Review

Recommendation

Slippage parameter should be included in the function call and not be 0.

Duplicate of #673