ICON: Intent-Context Coupling for Efficient Multi-Turn Jailbreak Attack
Xingwei Lin 1, Wenhao Lin 1, Sicong Cao 2, Jiahao Yu 3, Renke Huang 4, Lei Xue 4, Chunming Wu 1
Published on arXiv
2601.20903
Prompt Injection
OWASP LLM Top 10 — LLM01
Key Finding
Achieves a state-of-the-art average Attack Success Rate of 97.1% across eight commercial and open-source LLMs, outperforming prior multi-turn jailbreak baselines.
ICON (Intent-Context Coupling)
Novel technique introduced
Multi-turn jailbreak attacks have emerged as a critical threat to Large Language Models (LLMs), bypassing safety mechanisms by progressively constructing adversarial contexts from scratch and incrementally refining prompts. However, existing methods suffer from the inefficiency of incremental context construction that requires step-by-step LLM interaction, and often stagnate in suboptimal regions due to surface-level optimization. In this paper, we characterize the Intent-Context Coupling phenomenon, revealing that LLM safety constraints are significantly relaxed when a malicious intent is coupled with a semantically congruent context pattern. Driven by this insight, we propose ICON, an automated multi-turn jailbreak framework that efficiently constructs an authoritative-style context via prior-guided semantic routing. Specifically, ICON first routes the malicious intent to a congruent context pattern (e.g., Scientific Research) and instantiates it into an attack prompt sequence. This sequence progressively builds the authoritative-style context and ultimately elicits prohibited content. In addition, ICON incorporates a Hierarchical Optimization Strategy that combines local prompt refinement with global context switching, preventing the attack from stagnating in ineffective contexts. Experimental results across eight SOTA LLMs demonstrate the effectiveness of ICON, achieving a state-of-the-art average Attack Success Rate (ASR) of 97.1\%. Code is available at https://github.com/xwlin-roy/ICON.
Key Contributions
- Characterizes the Intent-Context Coupling phenomenon: LLM safety constraints relax significantly when malicious intent is paired with a semantically congruent authoritative context pattern
- Proposes ICON, a multi-turn jailbreak framework using prior-guided semantic routing to directly construct adversarial context sequences without iterative from-scratch construction
- Introduces a Hierarchical Optimization Strategy combining local prompt refinement and global context switching to escape suboptimal attack regions