Yinpeng Dong
Author directory2026
Membership Inference in Fine-tuned Diffusion Language Models via Token-level Memorization Asymmetry
Shengfang Zhai | Leo Marchyok | Yuling Shi | Huanran Chen | Yinpeng Dong | Jiaheng Zhang | Sanghyun Hong
Findings of the Association for Computational Linguistics: EMNLP 2026
Shengfang Zhai | Leo Marchyok | Yuling Shi | Huanran Chen | Yinpeng Dong | Jiaheng Zhang | Sanghyun Hong
Findings of the Association for Computational Linguistics: EMNLP 2026
Diffusion language models (DLMs) have recently emerged as an alternative modeling paradigm to autoregressive LMs, offering advantages such as parallel generation and bidirectional context modeling. Despite growing interest in their generative capabilities, the privacy risks of DLMs remain underexplored. We identify a phenomenon termed token-level memorization asymmetry through theoretical analysis of diffusion training dynamics. Building on this finding, we propose Q-Skew, a quantile-weighted skewness-based indicator for membership inference on finetuned DLMs. Experiments across multiple fine-tuning datasets and models show that our method outperforms existing baselines. Moreover, we show that Q-Skew can also facilitate other privacy violations, such as PII extraction. Our findings reveal a previously underexplored privacy attack surface and highlight the need for systematic privacy evaluation of DLMs.
Before the Script, Set the Stage: How Worldview Simulation Amplifies Psychologically Grounded Persuasion in Multi-Turn Jailbreaking
Siyu Chen | Haoran Wang | Xiaojian Li | Yao Huang | Yinpeng Dong | Wei Xu
Findings of the Association for Computational Linguistics: EMNLP 2026
Siyu Chen | Haoran Wang | Xiaojian Li | Yao Huang | Yinpeng Dong | Wei Xu
Findings of the Association for Computational Linguistics: EMNLP 2026
Multi-turn jailbreak attacks demonstrate that harmful intent can be distributed across dialogue, yet existing methods obscure what conversational mechanisms drive vulnerability. We introduce Blueprint, a safety-evaluation framework that separates a factorized social-influence strategy space from WorldviewSim, a cross-turn situational context module. Monte Carlo Tree Search optimizes turn-level combinations of 18 theory-grounded influence factors across a four-turn trajectory. Across six frontier models, Blueprint achieves near-ceiling attack success rates on major open-weight and proprietary models, while requiring the fewest average queries (2.46). The resulting trajectories further reveal model-specific vulnerability among resistant targets: each responds to distinct influence factors and strategy transitions, yet all share a common recovery pathway. Specifically, shifting toward concrete, executable task framing consistently escapes hard-refusal states. Ablations confirm that operational cues matter most: making requests actionable has the largest impact, gain framing is unusually potent, and some legitimacy appeals can backfire. These findings suggest that robust multi-turn safety requires monitoring not only harmful content, but also how dialogue state makes unsafe requests appear concrete and locally executable. The code is open-sourced at: https://github.com/charlottec1583/Blueprint.
2025
Libra-Leaderboard: Towards Responsible AI through a Balanced Leaderboard of Safety and Capability
Haonan Li | Xudong Han | Zenan Zhai | Honglin Mu | Hao Wang | Zhenxuan Zhang | Yilin Geng | Shom Lin | Renxi Wang | Artem Shelmanov | Xiangyu Qi | Yuxia Wang | Donghai Hong | Youliang Yuan | Meng Chen | Haoqin Tu | Fajri Koto | Cong Zeng | Tatsuki Kuribayashi | Rishabh Bhardwaj | Bingchen Zhao | Yawen Duan | Yi Liu | Emad A. Alghamdi | Yaodong Yang | Yinpeng Dong | Soujanya Poria | Pengfei Liu | Zhengzhong Liu | Hector Xuguang Ren | Eduard Hovy | Iryna Gurevych | Preslav Nakov | Monojit Choudhury | Timothy Baldwin
Proceedings of the 2025 Conference of the Nations of the Americas Chapter of the Association for Computational Linguistics: Human Language Technologies (System Demonstrations)
Haonan Li | Xudong Han | Zenan Zhai | Honglin Mu | Hao Wang | Zhenxuan Zhang | Yilin Geng | Shom Lin | Renxi Wang | Artem Shelmanov | Xiangyu Qi | Yuxia Wang | Donghai Hong | Youliang Yuan | Meng Chen | Haoqin Tu | Fajri Koto | Cong Zeng | Tatsuki Kuribayashi | Rishabh Bhardwaj | Bingchen Zhao | Yawen Duan | Yi Liu | Emad A. Alghamdi | Yaodong Yang | Yinpeng Dong | Soujanya Poria | Pengfei Liu | Zhengzhong Liu | Hector Xuguang Ren | Eduard Hovy | Iryna Gurevych | Preslav Nakov | Monojit Choudhury | Timothy Baldwin
Proceedings of the 2025 Conference of the Nations of the Americas Chapter of the Association for Computational Linguistics: Human Language Technologies (System Demonstrations)
As large language models (LLMs) continue to evolve, leaderboards play a significant role in steering their development. Existing leaderboards often prioritize model capabilities while overlooking safety concerns, leaving a significant gap in responsible AI development. To address this gap, we introduce Libra-Leaderboard, a comprehensive framework designed to rank LLMs through a balanced evaluation of performance and safety. Combining a dynamic leaderboard with an interactive LLM arena, Libra-Leaderboard encourages the joint optimization of capability and safety. Unlike traditional approaches that average performance and safety metrics, Libra-Leaderboard uses a distance-to-optimal-score method to calculate the overall rankings. This approach incentivizes models to achieve a balance rather than excelling in one dimension at the expense of some other ones. In the first release, Libra-Leaderboard evaluates 26 mainstream LLMs from 14 leading organizations, identifying critical safety challenges even in state-of-the-art models.
AutoBreach: Universal and Adaptive Jailbreaking with Efficient Wordplay-Guided Optimization via Multi-LLMs
Jiawei Chen | Xiao Yang | Zhengwei Fang | Yu Tian | Yinpeng Dong | Zhaoxia Yin | Hang Su
Findings of the Association for Computational Linguistics: NAACL 2025
Jiawei Chen | Xiao Yang | Zhengwei Fang | Yu Tian | Yinpeng Dong | Zhaoxia Yin | Hang Su
Findings of the Association for Computational Linguistics: NAACL 2025
Recent studies show that large language models (LLMs) are vulnerable to jailbreak attacks, which can bypass their defense mechanisms. However, existing jailbreak research often exhibits limitations in universality, validity, and efficiency. Therefore, we rethink jailbreaking LLMs and define three key properties to guide the design of effective jailbreak methods. We introduce AutoBreach, a novel black-box approach that uses wordplay-guided mapping rule sampling to create universal adversarial prompts. By leveraging LLMs’ summarization and reasoning abilities, AutoBreach minimizes manual effort. To boost jailbreak success rates, we further suggest sentence compression and chain-of-thought-based mapping rules to correct errors and wordplay misinterpretations in target LLMs. Also, we propose a two-stage mapping rule optimization that initially optimizes mapping rules before querying target LLMs to enhance efficiency. Experimental results indicate AutoBreach efficiently identifies security vulnerabilities across various LLMs (Claude-3, GPT-4, etc.), achieving an average success rate of over 80% with fewer than 10 queries. Notably, the adversarial prompts generated by AutoBreach for GPT-4 can directly bypass the defenses of the advanced commercial LLM GPT o1-preview, demonstrating strong transferability and universality.
Exploring the Generalizability of Factual Hallucination Mitigation via Enhancing Precise Knowledge Utilization
Siyuan Zhang | Yichi Zhang | Yinpeng Dong | Hang Su
Findings of the Association for Computational Linguistics: EMNLP 2025
Siyuan Zhang | Yichi Zhang | Yinpeng Dong | Hang Su
Findings of the Association for Computational Linguistics: EMNLP 2025
Large Language Models (LLMs) often struggle to align their responses with objective facts, resulting in the issue of factual hallucinations, which can be difficult to detect and mislead users without relevant knowledge. Although post-training techniques have been employed to mitigate the issue, existing methods usually suffer from poor generalization and trade-offs in other different capabilities. In this paper, we propose to address these by directly augmenting LLM’s fundamental ability to precisely leverage its knowledge and introduce PKUE (Precise Knowledge Utilization Enhancement), which fine-tunes the model on self-generated responses to precise and simple factual questions through preference optimization. Furthermore, we construct FactualBench, a comprehensive and precise factual QA dataset containing 181k Chinese data spanning 21 domains, to facilitate both evaluation and training. Extensive experiments demonstrate that PKUE significantly improves LLM overall performance, with consistent enhancement across factual tasks of various forms, general tasks beyond factuality, and tasks in different language.
Breaking the Ceiling: Exploring the Potential of Jailbreak Attacks through Expanding Strategy Space
Yao Huang | Yitong Sun | Shouwei Ruan | Yichi Zhang | Yinpeng Dong | Xingxing Wei
Findings of the Association for Computational Linguistics: ACL 2025
Yao Huang | Yitong Sun | Shouwei Ruan | Yichi Zhang | Yinpeng Dong | Xingxing Wei
Findings of the Association for Computational Linguistics: ACL 2025
Large Language Models (LLMs), despite advanced general capabilities, still suffer from numerous safety risks, especially jailbreak attacks that bypass safety protocols. Understanding these vulnerabilities through black-box jailbreak attacks, which better reflect real-world scenarios, offers critical insights into model robustness. While existing methods have shown improvements through various prompt engineering techniques, their success remains limited against safety-aligned models, overlooking a more fundamental problem: the effectiveness is inherently bounded by the predefined strategy spaces. However, expanding this space presents significant challenges in both systematically capturing essential attack patterns and efficiently navigating the increased complexity. To better explore the potential of expanding the strategy space, we address these challenges through a novel framework that decomposes jailbreak strategies into essential components based on the Elaboration Likelihood Model (ELM) theory and develops genetic-based optimization with intention evaluation mechanisms. To be striking, our experiments reveal unprecedented jailbreak capabilities by expanding the strategy space: we achieve over 90% success rate on Claude-3.5 where prior methods completely fail, while demonstrating strong cross-model transferability and surpassing specialized safeguard models in evaluation accuracy. The code is open-sourced at: https://github.com/Aries-iai/CL-GSO.
Search
Fix author
Co-authors
- Yao Huang 2
- Hang Su 2
- Yichi Zhang 2
- Emad A. Alghamdi 1
- Timothy Baldwin 1
- Rishabh Bhardwaj 1
- Huanran Chen 1
- Jiawei Chen 1
- Meng Chen 1
- Siyu Chen 1
- Monojit Choudhury 1
- Yawen Duan 1
- Zhengwei Fang 1
- Yilin Geng 1
- Iryna Gurevych 1
- Xudong Han 1
- Donghai Hong 1
- Sanghyun Hong 1
- Eduard Hovy 1
- Fajri Koto 1
- Tatsuki Kuribayashi 1
- Haonan Li 1
- Xiaojian Li 1
- Shom Lin 1
- Pengfei Liu 1
- Yi Liu 1
- Zhengzhong Liu 1
- Leo Marchyok 1
- Honglin Mu 1
- Preslav Nakov 1
- Soujanya Poria 1
- Xiangyu Qi 1
- Hector Xuguang Ren 1
- Shouwei Ruan 1
- Artem Shelmanov 1
- Yuling Shi 1
- Yitong Sun 1
- Yu Tian 1
- Haoqin Tu 1
- Hao Wang 1
- Haoran Wang 1
- Renxi Wang 1
- Yuxia Wang 1
- Xingxing Wei 1
- Wei Xu 1
- Xiao Yang 1
- Yaodong Yang (杨耀东) 1
- Zhaoxia Yin 1
- Youliang Yuan 1
- Cong Zeng 1
- Shengfang Zhai 1
- Zenan Zhai 1
- Jiaheng Zhang 1
- Siyuan Zhang 1
- Zhenxuan Zhang 1
- Bingchen Zhao 1