“Good enough” emulation: Fuzzing a single thread to uncover vulnerabilities

This Cisco Talos research report describes how the author bypassed hardware code read-out protection by emulating only the Modbus-processing thread of a Socomec DIRIS M-70 gateway using Unicorn (with AFL) and Qiling to fuzz and analyze Modbus handling, which uncovered six DoS vulnerabilities (several CVEs) that were responsibly disclosed and patched by the vendor; the write-up outlines the emulation/fuzzing workflow, tooling choices, triage steps, and recommends Qiling for future single-thread emulation projects.