This paper presents research on the vulnerability of an inference model that generates Chain of Thought (CoT) tokens to jailbreak attacks. Unlike existing language models, which make rejection decisions at the prompt-response boundary, we found evidence that the DeepSeek-R1-Distill-Llama-8B model makes rejection decisions within the CoT generation process. We identified a linear direction (attention direction) in the activation space during CoT token generation that predicts whether the model will reject or accept. This direction corresponds to a pattern of deliberate inference in the generated text. Removing this direction from the model activations increases harmful acceptance, effectively enabling the model to be jailbroken. We also demonstrate that the final output can be controlled by manipulating CoT token activations alone, and incorporating this direction into a prompt-based attack improves the success rate. Consequently, our findings suggest that the chain of thoughts itself represents a promising new target for adversarial manipulation of inference models.