With the increasing popularity of blockchain, automatically detecting vulnerabilities in smart contracts is becoming a significant problem. Prior research mainly identifies smart contract vulnerabilities without considering the interactions between multiple contracts. Due to the lack of analyzing the fine-grained contextual information during cross-contract invocations, existing approaches often produced a large number of false positives and false negatives.

This paper proposes SmartDagger, a new framework for detecting cross-contract vulnerability through static analysis at the bytecode level. SmartDagger integrates a set of novel mechanisms to ensure its effectiveness and efficiency for cross-contract vulnerability detection. Particularly, SmartDagger effectively recovers the contract attribute information from the smart contract bytecode, which is critical for accurately identifying cross-contract vulnerabilities. Besides, instead of performing the typical whole-program analysis which is heavy-weight and time-consuming, SmartDagger selectively analyzes a subset of functions and reuses the data-flow results, which helps to improve its efficiency. Our further evaluation over a manually labelled dataset showed that SmartDagger significantly outperforms other state-of-the-art tools (i.e., Oyente, Slither, Osiris, and Mythril) for detecting cross-contract vulnerabilities. In addition, running SmartDagger over a randomly selected dataset of 250 smart contracts in the real-world, SmartDagger detects 11 cross-contract vulnerabilities, all of which are missed by prior tools.