Nguyen Viet Anh
2026
Three Minds, One Legend: Jailbreak Large Reasoning Model with Adaptive Stacked Ciphers
Nguyen Viet Anh | Shiqian Zhao | Gia Dao | Runyi Hu | Yi Xie | Xiaobao Wu | Anh Tuan Luu
Findings of the Association for Computational Linguistics: ACL 2026
Nguyen Viet Anh | Shiqian Zhao | Gia Dao | Runyi Hu | Yi Xie | Xiaobao Wu | Anh Tuan Luu
Findings of the Association for Computational Linguistics: ACL 2026
Recently, Large Reasoning Models (LRMs) have demonstrated superior logical capabilities compared to traditional Large Language Models (LLMs), gaining significant attention. Despite their impressive performance, the potential for stronger reasoning abilities to introduce more severe security vulnerabilities, though pointed out by some previous works, remains largely underexplored. Existing jailbreak methods often struggle to balance effectiveness with robustness against adaptive safety mechanisms. In this work, we propose SEAL, a novel jailbreak attack that targets LRMs through an adaptive encryption pipeline designed to override their reasoning processes and evade potential adaptive alignment. Specifically, SEAL introduces a stacked encryption approach that combines multiple ciphers to overwhelm the model’s reasoning capabilities, effectively bypassing built-in safety mechanisms. To further prevent LRMs from developing countermeasures, we incorporate two dynamic strategies—random and adaptive—that adjust the cipher length, order, and combination. Extensive experiments on real-world reasoning models, including DeepSeek-R1, Claude Sonnet, and OpenAI GPT-o4-mini, validate the effectiveness of our approach. Notably, SEAL achieves an attack success rate of 85.6% on GPT o4-mini, outperforming state-of-the-art baselines by a significant margin of 17.2%. Warning: This paper contains examples of inappropriate, offensive, and harmful content
2025
Enhancing Multimodal Entity Linking with Jaccard Distance-based Conditional Contrastive Learning and Contextual Visual Augmentation
Cong-Duy T Nguyen | Xiaobao Wu | Thong Thanh Nguyen | Shuai Zhao | Khoi M. Le | Nguyen Viet Anh | Feng Yichao | Anh Tuan Luu
Proceedings of the 2025 Conference of the Nations of the Americas Chapter of the Association for Computational Linguistics: Human Language Technologies (Volume 1: Long Papers)
Cong-Duy T Nguyen | Xiaobao Wu | Thong Thanh Nguyen | Shuai Zhao | Khoi M. Le | Nguyen Viet Anh | Feng Yichao | Anh Tuan Luu
Proceedings of the 2025 Conference of the Nations of the Americas Chapter of the Association for Computational Linguistics: Human Language Technologies (Volume 1: Long Papers)
Previous research on multimodal entity linking (MEL) has primarily employed contrastive learning as the primary objective. However, using the rest of the batch as negative samples without careful consideration, these studies risk leveraging easy features and potentially overlook essential details that make entities unique. In this work, we propose JD-CCL (Jaccard Distance-based Conditional Contrastive Learning), a novel approach designed to enhance the ability to match multimodal entity linking models. JD-CCL leverages meta-information to select negative samples with similar attributes, making the linking task more challenging and robust. Additionally, to address the limitations caused by the variations within the visual modality among mentions and entities, we introduce a novel method, CVaCPT (Contextual Visual-aid Controllable Patch Transform). It enhances visual representations by incorporating multi-view synthetic images and contextual textual representations to scale and shift patch representations. Experimental results on benchmark MEL datasets demonstrate the strong effectiveness of our approach.