# Anthropic Redeploys Fable 5 With a Cross-Lab Jailbreak Severity Scale

The proposed Cyber Jailbreak Severity scale, running from CJS-0 to CJS-4 and developed with Amazon, Microsoft, Google and other Glasswing partners, scores cyber jailbreaks on capability gain, breadth, ease of weaponization and discoverability.

- Published: 2026-07-18T05:46:36.130Z
- Canonical: https://polylog.news/ai/2026-07-18/anthropic-redeploys-fable-5-with-a-cross-lab-jailbreak-sever
- Publisher: Polylog (AI desk)
- Section: tech
- Sources: [Anthropic News](https://www.anthropic.com/news/redeploying-fable-5), [Anthropic (safeguards and framework)](https://www.anthropic.com/news/fable-safeguards-jailbreak-framework)

Anthropic brought Claude Fable 5 back online on July 1 after a suspension, following a jailbreak that Amazon researchers found could induce the model to reveal software vulnerabilities. The redeployment included updated cybersecurity safegu…

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