arXiv Computation and Language

IHDec: Divergence-Steered Contrastive Decoding for Securing Multi-Turn Instruction Hierarchies

Large Language Models often fail to respect instruction hierarchies in multi-turn settings, sometimes following lower-priority directives over higher ones. The authors formalize this failure using a Jensen‑Shannon Divergence framework and introduce IHDec, a contrastive decoding method that detects hierarchy violations at the token level and suppresses subordinate role influence without any fine‑tuning. Experiments show IHDec outperforms training‑based baselines, maintains overall response quality, improves safety against adversarial prompts, and scales well with larger models.

Hugging Face Trending Papers
Jul 2

Safety Targeted Embedding Exploit via Refinement

Safety training for large language models (LLMs) is conducted predominantly in English, leaving uncertain how well safety mechanisms generalize to low-resource languages and mixed-language code-switching. We show that this creates an epistemic gap in which models confidently generate harmful responses for inputs that fall outside the distribution of their safety training.

arXiv AI
Sep 10

Many-Tier Instruction Hierarchy in LLM Agents

The paper introduces Many-Tier Instruction Hierarchy (ManyIH), a new framework for resolving conflicts among instructions with arbitrarily many privilege levels in large language model agents. It presents ManyIH-Bench, a benchmark featuring 853 agentic tasks that require navigating up to 12 levels of conflicting instructions across 46 real-world agents. Experiments show current models achieve only about 40% accuracy when instruction conflict scales, highlighting a gap in fine-grained, scalable conflict resolution.

By Jingyu Zhang, Tianjian Li, William Jurayj, Hongyuan Zhan, Benjamin Van Durme, Daniel Khashabi
arXiv Computation and Language
Sep 25

Combating Instruction Conflict via Energy-Driven Latent Conflict Detection

The paper introduces ELCD, a latent conflict detector that verifies LLM outputs after generation to catch instruction conflicts that static input checks miss. ELCD builds a hidden-state representation from the final-token embedding and the mean-pooled response embedding, then trains a pairwise margin ranking objective to distinguish compliant from drifting responses. Experiments on five large language models show ELCD outperforms baselines, boosting PR-AUC for Llama‑2‑7B by ~30 percentage points and cutting FPR95 for Mistral‑7B to 2.67%.

By Mingyu Ma, Yuxin Wu, Jingbo Wang, Tianxiao Huang, Leixin Sun, Xiaochuan Shi
arXiv AI
Aug 26

Semantic Overlays: Mitigating Prompt Injection with Annotations Beyond Tokens and Steering Vectors

The paper introduces Semantic Overlays, a steering technique that adds non‑textual annotations to a language model’s input by applying learned adapters at specific prefill positions. These overlays create an out‑of‑band channel that encodes span identity and complex semantics, enabling the model to interpret marked text differently—such as rewriting code in a specified language or ignoring executable instructions. Experiments show that Semantic Overlays dramatically reduce prompt‑injection success rates while preserving model utility and readability of marked spans.

By Joshua Penman