EVulHunter: Detecting Fake Transfer Vulnerabilities for EOSIO's Smart Contracts at Webassembly-level

TL;DR

EVulHunter is a static analysis tool designed to automatically detect fake transfer vulnerabilities in EOSIO WebAssembly smart contracts, addressing a critical security gap in blockchain applications.

Contribution

This paper introduces EVulHunter, the first automated tool for detecting specific vulnerabilities in EOSIO's WebAssembly smart contracts, focusing on fake transfer issues.

Findings

Successfully detects fake transfer vulnerabilities in EOSIO WASM code

Operates efficiently with high accuracy in identifying security flaws

Available as an open-source tool on GitHub

Abstract

As one of the representative Delegated Proof-of-Stake (DPoS) blockchain platforms, EOSIO's ecosystem grows rapidly in recent years. A number of vulnerabilities and corresponding attacks of EOSIO's smart contracts have been discovered and observed in the wild, which caused a large amount of financial damages. However, the majority of EOSIO's smart contracts are not open-sourced. As a result, the WebAssembly code may become the only available object to be analyzed in most cases. Unfortunately, current tools are web-application oriented and cannot be applied to EOSIO WebAssembly code directly, which makes it more difficult to detect vulnerabilities from those smart contracts. In this paper, we propose \toolname, a static analysis tool that can be used to detect vulnerabilities from EOSIO WASM code automatically. We focus on one particular type of vulnerabilities named \textit{fake-transfer}, and the exploitation of such vulnerabilities has led to millions of dollars in damages. To the best of our knowledge, it is the first attempt to build an automatic tool to detect vulnerabilities of EOSIO's smart contracts. The experimental results demonstrate that our tool is able to detect fake transfer vulnerabilities quickly and precisely. EVulHunter is available on GitHub\footnote{Tool and benchmarks: https://github.com/EVulHunter/EVulHunter} and YouTube\footnote{Demo video: https://youtu.be/5SJ0ZJKVZvw}.