Summary

Vulnerability Details

According to the fact that EIP-20 states that zero-valued transfers must be accepted.

Checking non-zero transfer values can avoid an expensive external call and save gas.
While this is done at some places, it’s not consistently done in the solution.

There are 2 instances of this issue:

• Adding a non-zero-value check for success = IERC20(tokenCollateralAddress).transferFrom(msg.sender,address(this),amountCollateral) at the beginning of DSCEngine.depositCollateral(address,uint256)

• Adding a non-zero-value check for success = IERC20(tokenCollateralAddress).transfer(to,amountCollateral) at the beginning of DSCEngine._redeemCollateral(address,address,address,uint256)

Impact

Tools Used

Recommendations

Consider adding a non-zero-value check at the beginning of function.