Mining Characteristics of Vulnerable Smart Contracts Across Lifecycle Stages

Smart contracts are the cornerstone of decentralized applications and financial protocols, which extend the application of digital currency transactions. The applications and financial protocols introduce significant security challenges, resulting in substantial economic losses. Existing solutions predominantly focus on code vulnerabilities within smart contracts, accounting for only 50% of security incidents. Therefore, a more comprehensive study of security issues related to smart contracts is imperative. The existing empirical research realizes the static analysis of smart contracts from the perspective of the lifecycle and gives the corresponding measures for each stage. However, they lack the characteristic analysis of vulnerabilities in each stage and the distinction between the vulnerabilities. In this paper, we present the first empirical study on the security of smart contracts throughout their lifecycle, including deployment and execution, upgrade, and destruction stages. It delves into the security issues at each stage and provides at least seven feature descriptions. Finally, utilizing these seven features, five machine-learning classification models are used to identify vulnerabilities at different stages. The classification results reveal that vulnerable contracts exhibit distinct transaction features and ego network properties at various stages.