Y2k Finance contest - auditor0517's results

Lines of code

https://github.com/code-423n4/2022-09-y2k-finance/blob/ac3e86f07bc2f1f51148d2265cc897e8b494adf7/src/oracles/PegOracle.sol#L78

Vulnerability details

Impact

Wrong calculation of nowPrice in PegOracle.latestRoundData.

PegOracle.latestRoundData always returns nowPrice = 0 for normal 18 decimals tokens.

Proof of Concept

From the below formula, we can see nowPrice <= 10000.

File: 2022-09-y2k-finance\src\oracles\PegOracle.sol
67:         if (price1 > price2) {
68:             nowPrice = (price2 * 10000) / price1;
69:         } else {
70:             nowPrice = (price1 * 10000) / price2;
71:         }

After that, it's divided by 1e6 here and it will be 0 for normal 18 decimals tokens.

Tools Used

Manual Review

Recommended Mitigation Steps

We should change nowPrice / 1000000 to nowPrice / 10000.

Low Risk Issue

[L-01] Check address(0) before transfer funds (onlyAdmin functions)

• https://github.com/code-423n4/2022-09-y2k-finance/blob/ac3e86f07bc2f1f51148d2265cc897e8b494adf7/src/Vault.sol#L365

[L-02] require() should be used instead of assert()

• https://github.com/code-423n4/2022-09-y2k-finance/blob/ac3e86f07bc2f1f51148d2265cc897e8b494adf7/src/Vault.sol#L190

Non-critical Issues

[N-01] Typo

• https://github.com/code-423n4/2022-09-y2k-finance/blob/ac3e86f07bc2f1f51148d2265cc897e8b494adf7/src/Vault.sol#L265

0.5% = multiply by 1000 then divide by 5 => 0.5% = multiply by 5 then divide by 1000.

[N-02] Open TODOs

• https://github.com/code-423n4/2022-09-y2k-finance/blob/ac3e86f07bc2f1f51148d2265cc897e8b494adf7/src/Vault.sol#L196

[N-03] Event is missing indexed fields

• https://github.com/code-423n4/2022-09-y2k-finance/blob/ac3e86f07bc2f1f51148d2265cc897e8b494adf7/src/Controller.sol#L49
• https://github.com/code-423n4/2022-09-y2k-finance/blob/ac3e86f07bc2f1f51148d2265cc897e8b494adf7/src/SemiFungibleVault.sol#L35
• https://github.com/code-423n4/2022-09-y2k-finance/blob/ac3e86f07bc2f1f51148d2265cc897e8b494adf7/src/SemiFungibleVault.sol#L51
• https://github.com/code-423n4/2022-09-y2k-finance/blob/ac3e86f07bc2f1f51148d2265cc897e8b494adf7/src/VaultFactory.sol#L49
• https://github.com/code-423n4/2022-09-y2k-finance/blob/ac3e86f07bc2f1f51148d2265cc897e8b494adf7/src/VaultFactory.sol#L69
• https://github.com/code-423n4/2022-09-y2k-finance/blob/ac3e86f07bc2f1f51148d2265cc897e8b494adf7/src/rewards/RewardsFactory.sol#L39
• https://github.com/code-423n4/2022-09-y2k-finance/blob/ac3e86f07bc2f1f51148d2265cc897e8b494adf7/src/rewards/StakingRewards.sol#L52-L53