Here's one from last year:

https://www.anthropic.com/news/detecting-countering-misuse-a...

> The actor used AI to what we believe is an unprecedented degree. Claude Code was used to automate reconnaissance, harvesting victims’ credentials, and penetrating networks. Claude was allowed to make both tactical and strategic decisions, such as deciding which data to exfiltrate, and how to craft psychologically targeted extortion demands. Claude analyzed the exfiltrated financial data to determine appropriate ransom amounts, and generated visually alarming ransom notes that were displayed on victim machines.

tldr Claude was used to develop and execute malware.

Anthropic works with US agencies, it’s guaranteed Mythos is used for malware