July 29, 2026 · The Decoder
OpenAI open-sources Codex Security CLI to hunt code flaws
OpenAI released Codex Security CLI, an open-source command-line tool that automatically detects and fixes vulnerabilities in code repositories. Previously an internal project called "Aardvark," it has already helped fix more than 3,000 critical security flaws according to OpenAI.
Why it matters: This puts OpenAI in direct competition with Anthropic's Claude Security on a new front: using AI to automate code defense as attackers increasingly automate exploitation. Open-sourcing the tool, rather than keeping it closed, could spread AI-driven vulnerability scanning across the developer ecosystem faster than a paid product would.