Open Access

ARTICLE

IConFuzz: Constraint-Aware Argument Mutation for Effective Smart Contract Fuzzing

Hojin Choi, Jaeseung Choi^*

Department of Computer Science and Engineering, Sogang University, Seoul, Republic of Korea

* Corresponding Author: Jaeseung Choi. Email:

(This article belongs to the Special Issue: Advanced Security and Privacy in Blockchain Systems)

Computers, Materials & Continua 2026, 88(3), 89 https://doi.org/10.32604/cmc.2026.082577

Received 18 March 2026; Accepted 25 May 2026; Issue published 23 July 2026

Abstract

Recently, extensive research has focused on addressing the unique challenges of smart contract fuzzing. Nevertheless, existing fuzzers still struggle to generate adequate function call arguments that can explore the deep smart contract states. In this paper, we introduce novel classes of argument constraints that capture the inter-argument relationships required to exercise meaningful contract logic. We propose a static analysis algorithm to extract these constraints from Solidity source code. In addition, we design a constraint-aware argument mutation strategy that leverages the identified constraints to guide test case generation for smart contract fuzzing. We implement our approach in a fuzzer named IConFuzz. Our evaluation on realistic benchmarks with integer overflow, suicidal contract, and ether leakage vulnerabilities demonstrates that IConFuzz outperforms state-of-the-art testing tools in both the number of bugs discovered and the speed of bug detection.

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Keywords

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