Asymmetry contest - jasonxiale's results

Lines of code

https://github.com/code-423n4/2023-03-asymmetry/blob/44b5cd94ebedc187a08884a7f685e950e987261c/contracts/SafEth/derivatives/WstEth.sol#L86-L88

Vulnerability details

Impact

The function ethPerDerivative returns the price of WstETH in terms of stETH. The underlying token we desire is ETH. Since stETH does not have the same value as ETH, the output price incorrect.

Proof of Concept

The function ethPerDerivative only converts WstETH to stETH. Thus, ethPerDerivative() returns the value of WstETH in terms of stETH.

function ethPerDerivative(uint256 _amount) public view returns (uint256) {
    return IWStETH(WST_ETH).getStETHByWstETH(10 ** 18);
}

Tools Used

Manually

Recommended Mitigation Steps

Add extra steps to approximate the rate for converting stETH to ETH.

Lines of code

https://github.com/code-423n4/2023-03-asymmetry/blob/44b5cd94ebedc187a08884a7f685e950e987261c/contracts/SafEth/derivatives/Reth.sol#L240-L241

Vulnerability details

Impact

Reth.poolPrice uses the UniV3Pool.slot0 to calculate the price in terms of ETH. slot0 is the most recent data point and is therefore extremely easy to manipulate.

Proof of Concept

function poolPrice() private view returns (uint256) {
    address rocketTokenRETHAddress = RocketStorageInterface(
        ROCKET_STORAGE_ADDRESS
    ).getAddress(
            keccak256(
                abi.encodePacked("contract.address", "rocketTokenRETH")
            )
        );
    IUniswapV3Factory factory = IUniswapV3Factory(UNI_V3_FACTORY);
    IUniswapV3Pool pool = IUniswapV3Pool(
        factory.getPool(rocketTokenRETHAddress, W_ETH_ADDRESS, 500)
    );
    (uint160 sqrtPriceX96, , , , , , ) = pool.slot0();
    return (sqrtPriceX96 * (uint(sqrtPriceX96)) * (1e18)) >> (96 * 2);
}

Reth.poolPrice uses the UniV3Pool.slot0 to calculate the price in terms of ETH. slot0 is the most recent data point and is therefore extremely easy to manipulate.

Tools Used

VS

Recommended Mitigation Steps

Lines of code

https://github.com/code-423n4/2023-03-asymmetry/blob/44b5cd94ebedc187a08884a7f685e950e987261c/contracts/SafEth/derivatives/Reth.sol#L173-L174 https://github.com/code-423n4/2023-03-asymmetry/blob/44b5cd94ebedc187a08884a7f685e950e987261c/contracts/SafEth/derivatives/SfrxEth.sol#L74-L75

Vulnerability details

Impact

Division before before which can incur loss of precision, those two functions are used to swap token. So it could lead to token lost.

Proof of Concept

https://github.com/code-423n4/2023-03-asymmetry/blob/44b5cd94ebedc187a08884a7f685e950e987261c/contracts/SafEth/derivatives/Reth.sol#L173-L174

        uint256 minOut = ((((rethPerEth * msg.value) / 10 ** 18) *
            ((10 ** 18 - maxSlippage))) / 10 ** 18);

https://github.com/code-423n4/2023-03-asymmetry/blob/44b5cd94ebedc187a08884a7f685e950e987261c/contracts/SafEth/derivatives/SfrxEth.sol#L74-L75

    uint256 minOut = (((ethPerDerivative(_amount) * _amount) / 10 ** 18) *
        (10 ** 18 - maxSlippage)) / 10 ** 18;

Tools Used

Manual Review

Recommended Mitigation Steps

Consider always implementing multiplication first when it involves multiplication and division operation and division should always come last to increase precision.

Lines of code

https://github.com/code-423n4/2023-03-asymmetry/blob/44b5cd94ebedc187a08884a7f685e950e987261c/contracts/SafEth/SafEth.sol#L88 https://github.com/code-423n4/2023-03-asymmetry/blob/44b5cd94ebedc187a08884a7f685e950e987261c/contracts/SafEth/SafEth.sol#L149-L150

Vulnerability details

Impact

function stake and function rebalanceToWeights will generate some dust eth, which will be locked in the contract

Proof of Concept

Take function stake as an examle,

In L88-L91, the function will split the ETH into pieces, and deposit those pieces into different derivatives.

But after depist the ETH, the function doesn't send the dust back to user. And the dust ETH is locked in the contract

function stake() external payable {
    ...
    for (uint i = 0; i < derivativeCount; i++) {
        ...
        uint256 ethAmount = (msg.value * weight) / totalWeight; // split the ETH into pieces

        uint256 depositAmount = derivative.deposit{value: ethAmount}(); // deposit the ETH
    }
}

Tools Used

VS

Recommended Mitigation Steps