OpenAI is rolling out GPT-5.5-Cyber, a variant of its latest AI model, in limited preview for verified cybersecurity professionals and organizations through its Trusted Access for Cyber program.

Trusted Access for Cyber is OpenAI’s identity and trust-based access framework for cybersecurity users, designed to give verified defenders broader access to GPT-5.5’s cybersecurity capabilities for defensive tasks while maintaining restrictions on requests that could contribute to real-world harm.

ChatGPT 5.5 was released two weeks ago as OpenAI’s answer to Anthropic’s Claude Mythos model.

OpenAI describes GPT-5.5-Cyber as the most permissive version in its cybersecurity lineup, aimed at specialized authorized workflows for a smaller group of approved partners.

The company said the model includes stronger verification requirements and account-level controls, with preview access focused on advanced security operations such as authorized red teaming, penetration testing, and controlled validation.

“The initial preview of cyber-permissive models like GPT‑5.5‑Cyber is not intended to significantly increase cyber capability beyond GPT‑5.5 – it’s primarily trained to be more permissive on security-related tasks,” OpenAI wrote in a blog post.

“The differences between model access levels are most pronounced when comparing prompts and responses.”

OpenAI added that GPT-5.5 with Trusted Access for Cyber remains the recommended entry point for most security workflows.

“We’d like to help companies secure themselves, and we think it’s important to start work on this quickly,” Sam Altman, CEO of OpenAI, wrote on X.

OpenAI noted that during early testing, selected partners used GPT-5.5-Cyber to automate and expand red-teaming exercises on infrastructure systems and to validate high-severity vulnerabilities, which the company plans to document in a future technical deep dive as part of a responsible disclosure process.

“We expect to continue to accelerate defenders with various models, including both our flagship models through Trusted Access for Cyber, and with dedicated cyber models like GPT‑5.5‑Cyber and even more cyber-capable models in the future,” the company concluded.