OpenAI's GPT-5.5 matches Anthropic's Claude Mythos in cybersecurity capabilities
Here's what it means for you.
The competition in AI cybersecurity is heating up, impacting access and ethical considerations.
What happened
GPT-5.5 has been shown to match Claude Mythos in cyber attack simulations.
The Context
- GPT-5.5 is now available in ChatGPT and through API, while Claude Mythos is still limited to a small group.
- OpenAI's decision to limit access to GPT-5.5-Cyber contrasts with its earlier criticism of similar practices by Anthropic.
- The UK AI Security Institute's tests indicate that both models are capable of autonomously solving full network attack simulations.
Takeaway
The competitive landscape in AI cybersecurity is intensifying as leading models demonstrate advanced capabilities.
In-depth reporting on tech, policy, and science including AI.
"Respected analysis for technically savvy readers, including AI topics."
— A47 Editor
GPT-5.5 matches heavily hyped Mythos Preview in new cybersecurity tests
Recent cybersecurity tests indicate that OpenAI's GPT-5.5 has matched the performance of Anthropic's highly anticipated AI model, Mythos, suggesting that the cyber threat posed by Mythos is not unique to a single model.
In-depth coverage of hardware, software, science, and policy.
"Ars Technica provides expert technology news, hardware reviews, and analysis for a technically savvy audience."
— A47 Editor
GPT-5.5 matches heavily hyped Mythos Preview in new cybersecurity tests
Recent cybersecurity tests indicate that OpenAI's GPT-5.5 has matched the performance of Anthropic's highly anticipated AI model, Mythos, suggesting that the cyber threat posed by Mythos is not unique to a single model.
Biting coverage of AI/ML software and vendors.
"Known for skeptical, incisive reporting on enterprise tech."
— A47 Editor
OpenAI locks GPT-5.5-Cyber behind velvet rope despite slamming Anthropic for doing exactly that
OpenAI has announced a limited release of its new GPT-5.5-Cyber model, restricting access to a select group of 'cyber defenders,' despite previously criticizing Anthropic for similar gatekeeping practices. This move has sparked discussions about the ...
Daily AI news: models, tools, and policy.
"Independent outlet tracking the fast pace of AI."
— A47 Editor
GPT-5.5 matches Claude Mythos in cyber attack tests, UK AI Security Institute finds
OpenAI's GPT-5.5 has been evaluated by the UK AI Security Institute and found to match the performance of Anthropic's Claude Mythos in cyber attack simulations, marking it as the second AI model capable of autonomously solving such complex scenarios.