Scoop: NSA using Anthropic's Mythos despite blacklist

The National Security Agency is using https://www.axios.com/2026/04/16/anthropic-claude-opus-model-mythos" target="_blank">Anthropic's most powerful model yet, https://www.axios.com/2026/04/07/anthropic-mythos-preview-cybersecurity-risks" target="_blank">Mythos Preview, despite top officials at the Department of Defense — which oversees the NSA — insisting the company is a "supply chain risk," two sources tell Axios.

Why it matters: The government's cybersecurity needs appear to be outweighing the Pentagon's feud with Anthropic

• The department moved in February to cut off Anthropic and force its vendors to follow suit.

  That case is ongoing.

• The military is now broadening its use of Anthropic's tools while simultaneously arguing in court that using those tools threatens U.S. national security.

Breaking it down: Two sources said the NSA was using Mythos, while one said the model was also being used more widely within the department.

• It's unclear how the NSA is currently using Mythos, but other organizations with access to the model are using it predominantly to scan their own environments for exploitable security vulnerabilities.
• Anthropic restricted access to Mythos to around 40 organizations, contending that its offensive cyber capabilities were too dangerous to allow for a wider release.
• Anthropic only https://www.anthropic.com/glasswing" target="_blank">announced 12 of those organizations.

  One source said the NSA was among the unnamed agencies with access.

• The NSA's counterparts in the https://www.gov.uk/government/publications/ai-cyber-threats-open-letter-to-business-leaders/ai-cyber-threats-open-letter-to-business-leaders-html" target="_blank">U.K. have https://www.yahoo.com/news/articles/mi5-called-protect-britain-breakthrough-060000124.html" target="_blank">said they have access to the model through the country's AI Security Institute.

Driving the news: Anthropic CEO Dario Amodei https://www.axios.com/2026/04/17/anthropic-white-house-wiles-bessent-amodei" target="_blank">met White House chief of staff Susie Wiles and Treasury Secretary Scott Bessent on Friday to discuss the use of Mythos within government and Anthropic's wider plans and security practices.

• Sources said next steps after the meeting were expected to focus on how departments other than the Pentagon engage with the model.

  Both sides described the meeting as productive.

• Anthropic and the Pentagon declined to comment.

  The NSA and Office of the Director of National Intelligence did not respond to requests for comment.

Zoom out: The breakdown between the Pentagon and Anthropic came during tense contract renegotiations earlier this year.

• The department demanded Anthropic make its Claude model available for "all lawful purposes," while the company insisted on walling off mass domestic surveillance and the development of autonomous weapons.
• Some Defense officials still insist Anthropic's posture proved it can't be trusted to be there when the military needs it.

  Anthropic denies that.

• Others in the administration just want this fight to go away so they can utilize the cutting edge tools Anthropic is building.