Anthropic on Tuesday released a preview of its fresh frontier model, Mythos, which it says will be used by a slight coterie of partner organizations for cybersecurity work. In a previously leaked memo, the AI startup called the model one of its “most powerful” yet.

The model’s limited debut is part of a fresh security initiative, dubbed Project Glasswing, in which 12 partner organizations will deploy the model for the purposes of “defensive security work” and to secure critical software, Anthropic mentioned. While it was not specifically trained for cybersecurity work, the model will be used to scan both first-party and open source software systems for code vulnerabilities, the enterprise commented.

Anthropic claims that, over the past few weeks, Mythos identified “thousands of zero-day vulnerabilities, many of them critical.” Many of the vulnerabilities are one to two decades old, the business added.

Mythos is a general-purpose model for Anthropic’s Claude AI systems that the enterprise claims has strong agentic coding and reasoning skills. Anthropic’s frontier models are considered its most sophisticated and high-performance models, designed for more complex tasks, including agent-building and coding.

The partner organizations previewing Mythos as part of Project Glasswing include Amazon, Apple, Broadcom, Cisco, CrowdStrike, the Linux Foundation, Microsoft, and Palo Alto Networks. As part of the initiative, these partners will ultimately share what they’ve learned from using the model so that the rest of the tech industry can benefit from it. The preview is not going to be made generally available, Anthropic commented, though 40 organizations will gain access to the Mythos preview aside from the partnership.

Anthropic also claims that it has engaged in “ongoing discussions” with federal officials about the apply of Mythos, although one would have to imagine that those discussions are complicated by the fact that Anthropic and the Trump administration are currently locked in a legal battle after the Pentagon labeled the AI lab a supply-chain risk over Anthropic’s refusal to allow autonomous targeting or surveillance of U.S. citizens.

News of Mythos was originally leaked in a data security incident reported last month by Fortune. A draft blog about the model (then called “Capybara”) was left in an unsecured cache of documents available on a publicly inspectable data lake. The leak, which Anthropic Later attributed to “human error,” was originally spotted by security researchers. “‘Capybara’ is a recent name for a recent tier of model: larger and more intelligent than our Opus models — which were, until now, our most powerful,” the leaked document stated, adding later that it was “by far the most powerful AI model we’ve ever developed,” according to the report. 

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