HighGuard: Cross-Chain Business Logic Monitoring of Smart Contracts

TL;DR

HighGuard is a cross-chain monitoring tool that uses formal specifications to detect business logic violations in smart contracts, effectively identifying vulnerabilities without false positives or extra costs.

Contribution

It introduces a novel cross-chain monitoring approach using DCR graph models for verifying smart contract execution against formal specifications.

Findings

Successfully detected 54 exploits in evaluations.

Operates without code instrumentation or additional gas costs.

Effective in identifying business logic flaws across multiple blockchains.

Abstract

Logical flaws in smart contracts are often exploited, leading to significant financial losses. Our tool, HighGuard, detects transactions that violate business logic specifications of smart contracts. HighGuard employs dynamic condition response (DCR) graph models as formal specifications to verify contract execution against these models. It is capable of operating in a cross-chain environment for detecting business logic flaws across different blockchain platforms. We demonstrate HighGuard's effectiveness in identifying deviations from specified behaviors in smart contracts without requiring code instrumentation or incurring additional gas costs. By using precise specifications in the monitor, HighGuard achieves detection without false positives. Our evaluation, involving 54 exploits, confirms HighGuard's effectiveness in detecting business logic vulnerabilities. Our open-source implementation of HighGuard and a screencast of its usage are available at: https://github.com/mojtaba-eshghie/HighGuard https://www.youtube.com/watch?v=sZYVV-slDaY