Summary

NO STORAGE GAP FOR UPGRADEABLE CONTRACTS

Vulnerability Details

For UUPSUpgradeable and OwnableUpgradeable, which are upgradeable abstract contracts, inheriting contracts may introduce new variables. In order to be able to add new variables to the upgradeable abstract contract without causing storage collisions, a storage gap should be added to the upgradeable abstract contract.

If no storage gap is added, when the upgradable abstract contract introduces new variables, it may override the variables in the inheriting contract.

Impact

Tools Used

Recommendations

Consider adding a storage gap at the end of the upgradeable abstract contract