A Comparison of Security Analysis Methods for Smart Contracts Built on the Ethereum Blockchain

Blockchain technology is one of the superior technologies of recent times. It is a decentralized distributed ledger to record transactions in an immutable way. Smart contracts are digital contracts, i.e., an auto executable small piece of code, written to be deployed on the blockchain. Ethereum is a mostly used blockchain platform for writing and deploying the smart contract. The immutability feature of blockchain poses threats to smart contracts because if a smart contract is uploaded on the blockchain, it becomes immutable. The EVM design and solidity programming language pose some security issues, which should be analyzed properly. So smart contracts must be analyzed for vulnerabilities before deployment. Several smart contracts security analysis approaches are proposed in the literature based on symbolic execution, taint analysis, formal verification, rule-based pattern detection, etc. A comparative study of the above techniques is performed in this paper, which will help the researchers select an efficient method to analyze the Ethereum smart contracts and pave the way for future research directions.