OpenAI Expands Cyber Defense AI With GPT-5.5-Cyber Model
SAN FRANCISCO — OpenAI on Wednesday expanded its Trusted Access for Cyber program with GPT-5.5 and a specialized GPT-5.5-Cyber variant for verified security researchers and cyber defenders focused on vulnerability research and critical infrastructure protection.
GPT-5.5-Cyber is designed as a purpose-built tool for defensive cyber operations. The model is available to vetted participants in the company’s Trusted Access program, which requires verification of credentials before granting access, according to OpenAI’s announcement.
The launch comes as competition intensifies between leading U.S. AI labs in cybersecurity applications. Axios characterized GPT-5.5-Cyber as a direct competitor to Anthropic’s Mythos platform, which has gained traction among cyber defenders.
The Wall Street Journal reported that the preview of OpenAI’s most advanced cyber model has raised concerns among security researchers and policymakers about dual-use risks — the potential for the same AI capabilities used defensively to be repurposed for offensive cyber operations. The debate reflects broader tensions in Washington over how to regulate AI systems with national security implications.
OpenAI’s Trusted Access for Cyber program is designed to mitigate those risks by restricting access to verified defenders. The program provides qualified cybersecurity professionals with early access to models optimized for tasks such as identifying software vulnerabilities, analyzing threat intelligence and protecting critical infrastructure systems.
Critical infrastructure protection has been identified as a top national security priority. OpenAI said the specialized models are intended to help defenders identify and patch vulnerabilities across sectors including energy, finance and healthcare.
OpenAI and Anthropic have both sought contracts with U.S. defense and intelligence agencies, and the GPT-5.5-Cyber launch extends the two companies’ competition into the cybersecurity AI market.
The dual-use nature of advanced cyber AI — capable of both defending and potentially attacking digital infrastructure — has drawn scrutiny from security researchers and policymakers, according to the Wall Street Journal, as lawmakers continue to debate AI safety legislation.
