What the vulnerability does
01Description
Polkadot Frontier is an Ethereum and EVM compatibility layer for Polkadot and Substrate. There are various account address types in Frontier, e.g. precompiled contracts, smart contracts, and externally owned accounts. Some EVM mechanisms should be unreachable by certain types of accounts for safety. For precompiles to be callable by smart contracts they must be explicitly configured as CallableByContract. If this configuration is absent, then the precompile should be unreachable via smart contract accounts. In commits prior to 0822030, the underlying implementation of CallableByContract which returned the AddressType was incorrect. It considered the contract address running under CREATE or CREATE2 to be AddressType::EOA rather than correctly as AddressType::Contract. The issue only affects users who use custom precompile implementations that utilize AddressType::EOA and AddressType::Contract. It's not directly exploitable in any of the predefined precompiles in Frontier. This is fixed in version 0822030.
