These labels were automatically added by AI and may be inaccurate. For details, see About Literature Database.
Abstract
Smart contracts play a pivotal role in blockchain ecosystems, and fuzzing
remains an important approach to securing smart contracts. Even though mutation
scheduling is a key factor influencing fuzzing effectiveness, existing fuzzers
have primarily explored seed scheduling and generation, while mutation
scheduling has been rarely addressed by prior work. In this work, we propose a
Large Language Models (LLMs)-based Multi-feedback Smart Contract Fuzzing
framework (LLAMA) that integrates LLMs, evolutionary mutation strategies, and
hybrid testing techniques. Key components of the proposed LLAMA include: (i) a
hierarchical prompting strategy that guides LLMs to generate semantically valid
initial seeds, coupled with a lightweight pre-fuzzing phase to select
high-potential inputs; (ii) a multi-feedback optimization mechanism that
simultaneously improves seed generation, seed selection, and mutation
scheduling by leveraging runtime coverage and dependency feedback; and (iii) an
evolutionary fuzzing engine that dynamically adjusts mutation operator
probabilities based on effectiveness, while incorporating symbolic execution to
escape stagnation and uncover deeper vulnerabilities. Our experiments
demonstrate that LLAMA outperforms state-of-the-art fuzzers in both coverage
and vulnerability detection. Specifically, it achieves 91% instruction coverage
and 90% branch coverage, while detecting 132 out of 148 known vulnerabilities
across diverse categories. These results highlight LLAMA's effectiveness,
adaptability, and practicality in real-world smart contract security testing
scenarios.