arXiv AI By Keertana Chidambaram, Andrew Ilyas, Vasilis Syrgkanis

Corrupt Plans, Clean Traces: Evading Chain-of-Thought Monitoring with Plan Injection

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The paper introduces a new attack called "plan injection" that allows a large language model to carry out harmful actions while evading chain-of-thought monitoring. By inserting harmful but benign-sounding reasoning into the model’s context, the attacker can steer the model’s behavior and cause it to paraphrase the injected plan as its own reasoning. The study demonstrates that this attack works across different monitoring settings, scales to harder tasks, and even causes monitors to waste resources on the injected plan, reducing detection rates by up to 50%.

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