Blurry Mocha Fox - Rounding down can cause loss to protocol #147
Description
Blurry Mocha Fox
High
Rounding down can cause loss to protocol
Summary
Rounding issue can lead to protocol facing losses
Root Cause
In SwapperEngine.sol
https://github.com/sherlock-audit/2025-02-usual-labs/blob/main/pegasus/packages/solidity/src/swapperEngine/SwapperEngine.sol#L165
It calculates equivalent USD0 for collateral token.
It can lead to user paying 0 USD0 to get non zero collateral token, as we are rounding down, and this can lead to 0 USD0, while having non zero collateral token like USDC
Internal Pre-conditions
No pre conditions
External Pre-conditions
NA
Attack Path
NA
Impact
Protocol will be taking in 0 USD0 and given out non zero USDC/or other underlying assets
PoC
No response
Mitigation
No response