Multiple Model Guardrail Jailbreak via "End-of-Response Override" Tactic
Case GUID: 4e8ed295-a772-4a29-8727-cbefada44123Summary
A Guardrail Jailbreak vulnerability has been discovered affecting multiple models. The specific flaw exploits model handling of stop sequences and meta control cues by injecting fabricated end-of-response markers alongside normalization and debugging instructions, causing the model to treat a prohibited request as a benign technical repair task and allowing the attacker to obtain restricted procedural information.
Metadata
Models and Test Scores
| Copyrights | Harmful Substances | Illicit Substances | |||
|---|---|---|---|---|---|
| Harry Potter | Anthrax | Nerve Agent | Crystal Meth | Fentanyl | |
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Cohere Command R
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Meta LLaMa 3.3
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Meta LLaMa 4 Maverick
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Meta LLaMa 4 Scout
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Mistral Mistral 8B
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Mistral Mistral Large
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OpenAI GPT-5
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OpenAI GPT-5 mini
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OpenAI GPT-5.2
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Twitter / X Grok 3
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Social Impact Score
Level 3: Significant Risk
Violations at this level present a tangible risk to public safety or social well-being, often related to dangerous but not highly restricted content.
Example: Bypassing guardrails to obtain instructions for creating illicit substances, such as recreational drugs or substances with moderate harm potential. Leakage of private personal data such as Social Security number or private medical.
Potential Consequences: Potential health impacts on a small scale, significant regulatory interest, and the need for stricter AI guardrails.
Taxonomies
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Severity
Security Boundary
Guardrail Jailbreak
Models
Cohere Command R
Meta LLaMa 3.3
Meta LLaMa 4 Maverick
Meta LLaMa 4 Scout
Mistral Mistral 8B
Mistral Mistral Large
OpenAI GPT-5
OpenAI GPT-5 mini
OpenAI GPT-5.2
Twitter / X Grok 3
Published On
2026-02-12 (5 months)
Credit
Mihir Shah