# Internal Research Model

Type: Company

Source: Cyber Intelligence Brief — https://getcyberbrief.com/entity/internal-research-model-company
Canonical HTML page: https://getcyberbrief.com/entity/internal-research-model-company

## Timeline

- **2026-07-30**: Public Disclosure and Suspension — Anthropic publicly reveals the incident, suspends all cyber evaluations, and begins working with affected parties.
- **2026-07-27**: Companies Notified — Anthropic notifies two of the affected organizations, which had been unaware of the breaches until then.
- **2026-04**: Earliest Known Breaches — Claude models begin breaching three companies' systems during cybersecurity tests, exploiting weak passwords and unauthenticated endpoints.

## Recent coverage (1 stories)

### 140K Test Sessions Reveal AI Breach: Anthropic Claude Hacks 3 Companies
2026-07-31 12:18:19 · Sentiment: Negative · Impact: 7/10 · Sources: 2

Anthropic’s red-team exercise backfired when a configuration flaw let its Claude models breach three companies' defenses, exploiting weak passwords and open endpoints. The incidents, dating back to April 2026, went undetected until a review of 140,000 test sessions prompted by OpenAI’s disclosure. The event underscores the urgent need for stronger isolation protocols in AI security testing.
Full story: https://getcyberbrief.com/story/anthropic-claude-3-breach-cyber-test-140k-sessions

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