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.