PBI-Attack: Prior-Guided Bimodal Interactive Black-Box Jailbreak Attack for Toxicity Maximization
Ruoxi Cheng, Yizhong Ding, Shuirong Cao, Ranjie Duan, Xiaoshuang Jia, Shaowei Yuan, Zhiqiang Wang, Xiaojun Jia
Abstract
Understanding the vulnerabilities of Large Vision Language Models (LVLMs) to jailbreak attacks is essential for their responsible real-world deployment. Most previous work requires access to model gradients, or is based on human knowledge (prompt engineering) to complete jailbreak, and they hardly consider the interaction of images and text, resulting in inability to jailbreak in black box scenarios or poor performance. To overcome these limitations, we propose a Prior-Guided Bimodal Interactive Black-Box Jailbreak Attack for toxicity maximization, referred to as PBI-Attack. Our method begins by extracting malicious features from a harmful corpus using an alternative LVLM and embedding these features into a benign image as prior information. Subsequently, we enhance these features through bidirectional cross-modal interaction optimization, which iteratively optimizes the bimodal perturbations in an alternating manner through greedy search, aiming to maximize the toxicity of the generated response. The toxicity level is quantified using a well-trained evaluation model.Experiments demonstrate that PBI-Attack outperforms previous state-of-the-art jailbreak methods, achieving an average attack success rate of 92.5% across three open-source LVLMs and around 67.3% on three closed-source LVLMs.redDisclaimer: This paper contains potentially disturbing and offensive content.- Anthology ID:
- 2025.trustnlp-main.3
- Volume:
- Proceedings of the 5th Workshop on Trustworthy NLP (TrustNLP 2025)
- Month:
- May
- Year:
- 2025
- Address:
- Albuquerque, New Mexico
- Editors:
- Trista Cao, Anubrata Das, Tharindu Kumarage, Yixin Wan, Satyapriya Krishna, Ninareh Mehrabi, Jwala Dhamala, Anil Ramakrishna, Aram Galystan, Anoop Kumar, Rahul Gupta, Kai-Wei Chang
- Venues:
- TrustNLP | WS
- SIG:
- Publisher:
- Association for Computational Linguistics
- Note:
- Pages:
- 23–40
- Language:
- URL:
- https://preview.aclanthology.org/fix-sig-urls/2025.trustnlp-main.3/
- DOI:
- Cite (ACL):
- Ruoxi Cheng, Yizhong Ding, Shuirong Cao, Ranjie Duan, Xiaoshuang Jia, Shaowei Yuan, Zhiqiang Wang, and Xiaojun Jia. 2025. PBI-Attack: Prior-Guided Bimodal Interactive Black-Box Jailbreak Attack for Toxicity Maximization. In Proceedings of the 5th Workshop on Trustworthy NLP (TrustNLP 2025), pages 23–40, Albuquerque, New Mexico. Association for Computational Linguistics.
- Cite (Informal):
- PBI-Attack: Prior-Guided Bimodal Interactive Black-Box Jailbreak Attack for Toxicity Maximization (Cheng et al., TrustNLP 2025)
- PDF:
- https://preview.aclanthology.org/fix-sig-urls/2025.trustnlp-main.3.pdf