---
id: 1656
title: "Differential fuzz testing upgradeable smart contracts with Diffusc"
source_domain: blog.trailofbits.com
source_url: "https://blog.trailofbits.com/2023/07/07/differential-fuzz-testing-upgradeable-smart-contracts-with-diffusc/"
published_at: "2023-07-07T11:00:33Z"
tags: ["web3", "smart-contracts", "defi", "fuzzing", "static-analysis", "blockchain", "slither", "echidna", "upgradeable-contracts", "diffusc"]
phying_url: "https://phying.com/item/1656"
lang: en
---

# Differential fuzz testing upgradeable smart contracts with Diffusc

## Summary

Trail of Bits introduces Diffusc, combining Slither static analysis with differential fuzz testing via Echidna to catch behavior changes in upgradeable smart contracts before on-chain upgrades.

## Intelligence Metadata

- **Sources:** blog.trailofbits.com
- **Published:** 2023-07-07T11:00:33Z
- **Original:** https://blog.trailofbits.com/2023/07/07/differential-fuzz-testing-upgradeable-smart-contracts-with-diffusc/
- **Phying News:** https://phying.com/item/1656