# Missing key zero value check Low/Info · Three Sigma · DeFi game · 23rd October, 2024 Finding L-1 of the CODEUP security review. - Report: /reports/codeup - Source: https://cdn.sanity.io/files/qoqld077/staging/d9e57830a75b5165fd56e8b88037de7986a165ec.pdf --- ### Description `gameETHForWithdrawRate` is set in `Codeup::constructor()` to `_gameETHPrice / 1000` but a zero check is missing. ### Recommendation Add the `_checkValue()` function to `gameETHForWithdrawRate = _checkValue(_gameETHPrice / 1000)`. --- Related findings: - [Missing key events when requesting withdrawals that could be important for the allocator bot](https://0xsimao.com/findings/yieldoor-iii-requesting-withdrawals-allocator-bot): Yieldoor LoopedVault Update - [KeyringCoreV2Base::registerKey() could check that validTo is equal to or bigger than block.timestamp](https://0xsimao.com/findings/keyring-ii-register-equal-bigger-timestamp): Keyring Credentials - [Attacker can block LayerZero channel due to missing check of minimum gas passed](https://0xsimao.com/findings/tapioca-dao-layer-zero-channel-gas): Tapioca DAO - [The check rewardSelector != ZERO BYTES4 && rewardDestination.isContract() could be improved](https://0xsimao.com/findings/felix-reward-zero-bytes4-improved): Felix Price Feeds