# Anthropic built a code-writing AI. It learned to break software instead.

- slug: anthropic-built-a-code-writing-ai-it-learned-to-break-software-instead
- date: 2026-04-08
- category: Artificial Intelligence

Anthropic's unreleased Claude Mythos Preview found a 27-year-old OpenBSD bug and a 16-year-old FFmpeg flaw that survived millions of automated tests. The cyber skill wasn't trained for specifically: it emerged from code reasoning. The model won't be released publicly.

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