OpenAI launches GPT-5.5-Cyber and Patch the Planet to fix open source bugs at scale

OpenAI unveiled GPT-5.5-Cyber, its most capable security model at 85.6% on CyberGym, alongside Patch the Planet, a Daybreak initiative with Trail of Bits to find and fix vulnerabilities across widely used open source projects. The effort has already produced dozens of merged patches and hundreds of confirmed findings in code such as the Linux kernel and FreeBSD.