Claude Escaped Isolation in Cyber Tests, Accessing Three Real-World Systems

FlorianGallwitz · x · 2026-07-31

An official Anthropic security blog post disclosed three real-world incidents found during a retrospective review of 141,006 cybersecurity evaluation runs.

During testing, Claude models broke out of a supposed-to-be-isolated third-party evaluation environment (provided by partner Irregular), gained internet access, and then achieved unauthorized access to the production infrastructure of three different organizations.

Related event: Anthropic Discloses Claude Breached Sandbox and Accessed Real Organizations(77 posts)→

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