Anthropic debuts a preview of Mythos’ powerful new AI model in a new cybersecurity initiative

Anthropic on Tuesday released a preview of its new frontier model, Mythos, which it says will be used by a small group of partner organizations for cybersecurity businesses. In a Previously leaked memothe AI ​​startup described this model as one of the “most powerful” to date.

Anthropic said the model’s limited appearance is part of a new 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. Although not specifically trained in cybersecurity work, the model will be used to scan first-party and open source software systems for code vulnerabilities, the company said.

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

Mythos is a general-purpose model for Anthropic’s Claude AI systems that the company claims has strong programming and logical thinking skills. Anthropic frontier models are the most important Advanced, high-performance models,Designed for more complex tasks, including agent building and coding.

Partner organizations previewing Mythos as part of Project Glasswing include Amazon, Apple, Broadcom, Cisco, CrowdStrike, Linux Foundation, Microsoft, and Palo Alto Networks. As part of the initiative, these partners will eventually share what they have learned from using the model so that the rest of the tech industry can benefit from it. Anthropic said the preview will not be generally available, though 40 organizations will be able to access the Mythos preview regardless of the partnership.

Anthropic also claims to have been involved in “ongoing discussions” with federal officials about the use of Mythos, though one has to imagine that these discussions are complicated by the fact that Anthropic and the Trump administration are currently closed In a legal battletoe After the Pentagon described the AI ​​laboratory as a supply chain risk Anthropic rejection To allow self-targeting or surveillance of American citizens.

The Mythos news 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 in a publicly inspectable data lake. The leak, which Anthropic later attributed to “human error,” was originally spotted by security researchers. “Capybara is a new name for a new level of model: larger and more intelligent than our Opus models — which were, by far, our most powerful,” the leaked document said, later adding that it was “by far the most powerful AI model we have ever developed,” according to the report.

In the leak, Anthropic claimed that its new model went far beyond the performance areas (such as “software coding, academic reasoning, and cybersecurity”) that its generic models currently cater to, and that it would likely pose a cybersecurity threat if it was weaponized by bad actors to find and exploit bugs (rather than fixing them, which is how Mythos would be deployed).

Last month for the company Accidentally exposed Nearly 2,000 source code files and more than half a million lines of code came across a bug made when releasing version 2.1.88 of its Claude Code software package. The company then Accidentally caused Thousands of code repositories on GitHub will be removed as they try to clean up the mess.

Correction April 7, 2026: An earlier version of this article incorrectly stated the number of partners working with Anthropic on Project Glasswing. There are 12 partner organizations, although a total of 40 will have access to the Mythos Preview.