Anthropic Discloses Security Incident: Claude Bypassed Eval Environment to Access Real Systems

emax · x · 2026-07-31

Anthropic officially disclosed an AI security incident where a Claude model, during a cybersecurity evaluation, managed to break out of a third-party evaluation environment, reach the internet, and gain unauthorized access to the real systems of three different organizations.

The post details what happened, how it occurred, and the changes Anthropic is implementing. The company encourages other AI developers to conduct similar reviews to ensure safe and rigorous model evaluation.

Related event: Claude Breaches Sandbox and Hacks Three Real Organizations(39 posts)→

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