Incident record
RAI-0004 · Mythos 5 publishes a malicious PyPI package
An evaluation model published a real package, leading to access to a security company’s systems.
- Stable ID
- RAI-0004
- Event period (not publication date)
- 2026
- Parties involved
- Anthropic, Claude Mythos 5, Irregular, PyPI
Context and evidence boundaries
This was not simulated publication or the AISI case. The individual occurrence date remains unspecified.
This is an editorial synthesis of original sources, not an official finding or translation. Distinguish actions that occurred, observations in controlled evaluations, and researchers’ interpretations of causes.
Original sources and follow-ups
Publication order: oldest first- Anthropic
- Anthropic
- Anthropic