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AII-1002-69317
ReportedReported by fewer than three independent publishers, with no official finding.

Researchers demonstrate jailbreak attack bypassing AI safety mechanisms

Researchers demonstrated a jailbreaking technique that exploits chain-of-thought reasoning in large language models to bypass safety guardrails. The method, tested on OpenAI, DeepSeek, Google, and Anthropic models, dramatically reduced rejection rates for harmful content in some cases.

24 February 2025 Β· OpenAI Β· Security and cyberattacks
24 February 2025
AII-1002-693172 sources ↓
Quick facts
Category
Security and cyberattacks
Source
DataBreachToday
Date
24 February 2025
Drafted by
Raidu Incident Detection

What happened

Researchers from Duke University, Accenture, and Taiwan's National Tsing Hua University developed a jailbreaking method called "Hijacking Chain-of-Thought" (H-CoT) to bypass safety mechanisms in large reasoning models.

The attack exploits how reasoning models display intermediate thinking steps by crafting adversarial prompts that override safety checks. Researchers created a dataset called Malicious-Educator containing prompts designed to manipulate the chain-of-thought reasoning process.

Reported impact

OpenAI's o1 model typically rejects over 99% of prompts related to child abuse or terrorism, but under an H-CoT attack, its rejection rate dropped to less than 2% in some cases.

Testing on OpenAI o1, o3, DeepSeek-R1, and Gemini 2.0 Flash Thinking showed rejection rates plummeting to less than 2 per cent in some cases. Anthropic acknowledged the issue in documentation for its Claude 3.7 Sonnet model.

Index analysis

The attack exploits a vulnerability in how reasoning models process and display their reasoning. The technique modifies the reasoning processes generated by large language models to convince them that harmful information is needed for legitimate purposes such as safety or compliance.

Classification

Category
Security and cyberattacks
Industry
Digital security
Harm status
Potential harm
Intent
Unintentional
Timing
Post-deployment
Failure modes
Jailbreak, Prompt injection, Content moderation failure
Consequences
None recorded
AI systems
OpenAI o1, OpenAI o3, DeepSeek-R1, Gemini 2.0 Flash Thinking, Claude 3.7 Sonnet

Sources and evidence

This record was researched and written by the Index, based on the following original reporting.

DataBreachToday
AI Hijacked: New Jailbreak Exploits Chain-of-Thought
25 February 2025
SGT Report
AI models can be hijacked to bypass in-built safety checks
26 February 2025