(A) survey on security of blockchain smart contracts

Abstract

A blockchain records transactions among users on a public ledger. It has become front and center of the technology discussion in recent year. A piece of code deployed on a ledger and executed automatically by nodes on the network is a smart contract. While smart contracts have enabled a variety of applications on blockchain, they may contain security vulnerabilities, leading to massive research on smart contract security. This paper presents a comprehensive survey over smart contract security by collecting 391 papers, extracting 146 relevant ones, and classifying them into four dominant topics with 11 subtopics. We further classify each topic and provide key insights from the perspective of smart contract security. Another contribution of this paper is to investigate the strengths and limitations of the papers. Based on the observation, we conclude with unsolved challenges and directions in future research of smart contract security.