Anthropic sets the terms of access, pricing, disclosure, and defensive-use framing for Claude Mythos Preview.
model governancerelease controlsecurity research
Entity log
High impactOfficial
Fortune: unauthorized Discord group retains continuous Mythos access as of April 23, breach enabled by prior Mercor data leak
Fortune reported that the Discord group that gained unauthorized access to Mythos on its announcement day still had continuous access as of April 23. The group exploited knowledge from a prior cyberattack on AI training startup Mercor, which gave members familiarity with Anthropic's URL conventions for unreleased models. The group had not used Mythos for cyberattacks but had been running the model continuously since gaining access.
Ongoing unauthorized access — not a one-time breach — means Anthropic's Glasswing gating strategy remains materially compromised while the company investigates, and traces the access vector to a supply-chain incident at a third-party AI startup.
Critical impactOfficial
Bloomberg: unauthorized users accessed Claude Mythos Preview; Anthropic confirms active investigation
Bloomberg News, citing documentation and a person familiar with the matter, reported that a small group of unauthorized users gained access to Anthropic's restricted Claude Mythos Preview through a third-party vendor environment on the day of its announcement. The group — communicating through a private Discord channel — provided Bloomberg with screenshots and a live demonstration of the model. An Anthropic spokesperson confirmed the company is investigating the report, stating there is no evidence its core systems were impacted or that activity extended beyond the vendor environment.
An unauthorized access incident directly challenges Anthropic's Project Glasswing gating strategy and raises questions about the robustness of access controls on a model its own safety team flagged as too dangerous for public release.
Critical impactOfficial
Anthropic announces Project Glasswing and Claude Mythos Preview
Anthropic announced a gated research preview of Claude Mythos Preview through Project Glasswing, naming launch partners and saying access was extended to over 40 additional organizations.
The announcement created the initial access map: named critical-infrastructure partners, unnamed additional organizations, cloud access channels, and explicit defensive-security positioning.
Entity alerts
Subscribe to alerts for Anthropic.
An email when this entity's evidence status or access log changes. Low volume. Unsubscribe any time.