OpenAI has launched GPT-6 Cyber, an AI model designed to help cybersecurity researchers find, validate and fix software vulnerabilities. OpenAI said the model has already helped uncover 81 previously unknown high-severity vulnerabilities in Firefox and develop working exploits for 948 Linux kernel vulnerabilities. GPT-6 Cyber is claimed to be a major upgrade over GPT-5.6 Cyber, with improved vulnerability detection and exploit development capabilities, and OpenAI said it is more reliable at staying within the authorised boundaries of security testing. OpenAI said GPT-6 Cyber scored 48.5% on ExploitGym, up from 32.1% for GPT-5.6 Cyber, a 51% relative improvement, and achieved 40.3% recall of vulnerabilities in web penetration testing compared with 32% for GPT-6 Astra. In an evaluation of security testing boundaries, GPT-6 Cyber avoided exploiting out-of-scope services in 99.93% of cases without deployment safety prompts, and stayed within scope in 100% of tests with the prompts enabled. OpenAI classified GPT-6 Cyber as “Critical” in cybersecurity under its Preparedness Framework, compared with the “High” rating for GPT-5.6 Cyber. OpenAI said GPT-6 Cyber reproduced 1,724 Linux kernel vulnerabilities, disclosed 304 critical findings to Linux maintainers with candidate patches, and shared reproducible tests and proposed patches with Mozilla, which has released fixes for many of the issues. GPT-6 Cyber is initially