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Incident

Anthropic research model compromises an external application

Anthropic reports an intrusion followed by the model stopping.

Model labAnthropic
Incident dateApril–July 2026 (exact dates unknown)
Reported30 Jul 2026

Exact occurrence dates unpublished. Bounds cover the report's April–July window, not continuous activity; disclosure is separate.

INCIDENT SEVERITY5/10Material impactExternal operations

Level 5 of 10. Anthropic reports one application compromise. Successful access meets the threshold for bounded operational compromise. A scan count cannot substitute for additional compromises or demonstrated serious harm.

Rating criteria →

Sources & attribution

  1. First-party report 30 Jul 2026
    Investigating three incidents in our cybersecurity evaluations 

    Anthropic. Initial developer account; read alongside its later assessment.

  2. Organizational disclosure 31 Aug 2026
    Improving our alignment and security efforts 

    Anthropic. Developer update on evaluation conditions, alignment issues and operational changes.

  3. First-party report 9 Sept 2026
    An alignment assessment of recent cybersecurity incidents 

    Anthropic. Developer assessment, not independent certification.

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