自动化引导确保多模态大语言模型的安全性
Automating Steering for Safe Multimodal Large Language Models
July 17, 2025
作者: Lyucheng Wu, Mengru Wang, Ziwen Xu, Tri Cao, Nay Oo, Bryan Hooi, Shumin Deng
cs.AI
摘要
近期,多模态大语言模型(MLLMs)的进展不仅解锁了强大的跨模态推理能力,也引发了新的安全隐患,尤其是在面对对抗性多模态输入时。为提升MLLMs在推理阶段的安全性,我们引入了一种模块化且自适应的推理时干预技术——AutoSteer,无需对基础模型进行任何微调。AutoSteer包含三大核心组件:(1) 一种新颖的安全意识评分(SAS),能自动识别模型内部各层中最具安全相关性的差异;(2) 一个自适应安全探测器,训练用于从中间表示中估计有害输出的可能性;(3) 一个轻量级的拒绝头(Refusal Head),在检测到安全风险时选择性介入,调节生成过程。在LLaVA-OV和Chameleon模型上,针对多种安全关键基准的实验表明,AutoSteer显著降低了文本、视觉及跨模态威胁的攻击成功率(ASR),同时保持了模型的通用能力。这些发现确立了AutoSteer作为一个实用、可解释且有效的框架,为多模态AI系统的安全部署提供了有力保障。
English
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.