Utopia Tech
Strategy1 min read

Anthropic’s Fable 5 Model Jailbroken Within Days

Fable 5 is the supposed safe version of Anthropic’s Mythos Preview, with guardrails to ensure that it can’t be used to create cyberattacks. Well, that restriction was bypassed within days.

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Utopia Tech

June 23, 2026 · 1 min read

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Fable 5 is the supposed safe version of Anthropic’s Mythos Preview, with guardrails to ensure that it can’t be used to create cyberattacks. Well, that restriction was bypassed within days.

Originally published at schneier.com

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