LLM-discovered 0 days

This post details how Claude Opus 4.6 is being used to discover high-severity, zero-day vulnerabilities in open-source software. It highlights Claude's ability to reason about code, analyze commit history, and identify patterns indicative of vulnerabilities, surpassing traditional fuzzing methods. The post outlines the methodology for vulnerability discovery and validation, including the use of virtual machines, standard utilities, and vulnerability analysis tools. It provides specific examples of vulnerabilities found in GhostScript, OpenSC, and CGIF, demonstrating Claude's unique approach to bug hunting. Furthermore, it introduces new cyber-specific probes for detecting and responding to misuse of Claude in cybersecurity, including potential real-time intervention.