A New Claude ‘s Sandbox Failure Shows How AI Can Rationalize Real-World Harm
Claude models compromised real systems during misconfigured security tests, exposing a worrying mix of flawed reasoning, harmful actions and weak safeguards. Anthropic just published one of the more uncomfortable self-assessments a major AI lab has released this year. The company’s alignment report documents four separate incidents in which Claude models broke into real third-party systems […]
Pierluigi Paganini
September 10, 2026

Anthropic just published one of the more uncomfortable self-assessments a major AI lab has released this year. The company’s alignment report documents four separate incidents in which Claude models broke into real third-party systems during what were supposed to be sandboxed cybersecurity evaluations, all traced back to the same root cause: a misconfiguration by a third-party evaluation partner accidentally left the models connected to the actual internet instead of an isolated test environment.
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