Automating Steering for Safe Multimodal Large Language Models
Lyucheng Wu, Mengru Wang, Ziwen Xu, Tri Cao, Nay Oo, Bryan Hooi, Shumin Deng
Abstract
Recent progress in Multimodal Large Language Models (MLLMs) has unlocked powerful cross-modal reasoning abilities, but also raised new safety concerns, particularly when faced with adversarial multimodal inputs. To improve the safety of MLLMs during inference, we introduce a modular and adaptive inference-time intervention technology, AutoSteer, without requiring any fine-tuning of the underlying model. AutoSteer incorporates three core components: (1) a novel Safety Awareness Score (SAS) that automatically identifies the most safety-relevant distinctions among the model’s internal layers; (2) an adaptive safety prober trained to estimate the likelihood of toxic outputs from intermediate representations; and (3) a lightweight Refusal Head that selectively intervenes to modulate generation when safety risks are detected. Experiments on LLaVA-OV and Chameleon across diverse safety-critical benchmarks demonstrate that AutoSteer significantly reduces the Attack Success Rate (ASR) for textual, visual, and cross-modal threats, while maintaining general abilities. These findings position AutoSteer as a practical, interpretable, and effective framework for safer deployment of multimodal AI systems.- Anthology ID:
- 2025.emnlp-main.41
- Volume:
- Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
- Month:
- November
- Year:
- 2025
- Address:
- Suzhou, China
- Editors:
- Christos Christodoulopoulos, Tanmoy Chakraborty, Carolyn Rose, Violet Peng
- Venue:
- EMNLP
- SIG:
- Publisher:
- Association for Computational Linguistics
- Note:
- Pages:
- 792–814
- Language:
- URL:
- https://preview.aclanthology.org/ingest-emnlp/2025.emnlp-main.41/
- DOI:
- Cite (ACL):
- Lyucheng Wu, Mengru Wang, Ziwen Xu, Tri Cao, Nay Oo, Bryan Hooi, and Shumin Deng. 2025. Automating Steering for Safe Multimodal Large Language Models. In Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing, pages 792–814, Suzhou, China. Association for Computational Linguistics.
- Cite (Informal):
- Automating Steering for Safe Multimodal Large Language Models (Wu et al., EMNLP 2025)
- PDF:
- https://preview.aclanthology.org/ingest-emnlp/2025.emnlp-main.41.pdf