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Anthropic says its AI model hacked three companies

Jul 31, 2026, 8:29am EDT
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An Anthropic logo.
Dado Ruvic/Illustration/Reuters

Anthropic said its Claude AI model hacked into three organizations during cybersecurity testing.

The announcement came after a “swarm” of OpenAI agents escaped confinement, gained internet access, and broke into at least five companies, eventually stealing the answers to a cyberoffense evaluation.

The latest breach is less dramatic than the previously announced one: OpenAI’s models found and exploited vulnerabilities to escape, while in Anthropic’s case a misunderstanding led to the agent’s cage essentially being left open.

But both point to a difficult future: Most commercial AI is connected to the internet anyway, so confinement is irrelevant, and open-weight models that can easily have any anti-cyber guardrails removed by bad actors are now nearly as capable as frontier products.

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