Physical adversarial attacks on vision systems are typically studied through scene manipulation, such as adversarial patches or projections, where the adversary controls what the camera observes. Camera-side attacks using stickers or auxiliary optics have also been explored, but they treat attacks as image-space perturbations from designed patterns. This misses how physical imperfections interact with scene-dependent lighting and optics. We identify a threat: passive lens-side damage that is persistent yet trigger-conditioned, producing optical artifacts that bias geometric inference under particular visual conditions. We instantiate this threat through Scratch-induced Lens Adversarial Streak Hijacking SLASH, a physical-world attack caused by small scratches on a camera lens or protective cover. Scratches interact with bright light sources and specular reflections to create structured streak artifacts that distort depth cues. Since the perturbation is fixed in the optical path but triggered by the scene, it is both persistent and selective. We formulate the attack in optical space, model the scratch pattern as a trigger-conditioned optical channel, and optimize one fixed configuration across diverse viewing conditions. We evaluate SLASH on monocular depth estimation and monocular 3D object detection in digital and real-world settings. Under the fixed-scratch constraint, directional depth shifts reach up to 32% relative error for monocular depth estimation, with consistent effects on monocular 3D object detection. Physical experiments confirm transfer to real camera recordings, inducing depth shifts above the model's natural prediction baseline. These findings reveal an attack surface where benign-looking hardware imperfections act as latent, scene-triggered adversarial mechanisms, challenging assumptions about physical robustness and motivating defenses for secure vision systems.

翻译：物理对抗攻击对视觉系统的研究通常通过场景操控进行，例如对抗性补丁或投影，其中攻击者控制相机观察的内容。使用贴纸或辅助光学器件的相机侧攻击也已被探索，但它们将攻击视为来自设计模式的图像空间扰动。这忽略了物理缺陷如何与场景依赖的光照和光学相互作用。我们识别出一种威胁：被动的镜头侧损伤是持久且触发条件化的，在特定视觉条件下产生光学伪影，从而偏差几何推理。我们通过划痕诱导的镜头对抗性条纹劫持（SLASH）来实例化这一威胁，这是一种由相机镜头或保护罩上的小划痕引起的物理世界攻击。划痕与明亮光源和镜面反射相互作用，产生结构化条纹伪影，扭曲深度线索。由于扰动固定在光学路径中但由场景触发，它既持久又具有选择性。我们在光学空间中制定攻击，将划痕模式建模为触发条件化的光学通道，并优化一个固定的配置以适应不同的观看条件。我们在数字和真实世界设置中评估了SLASH对单目深度估计和单目3D物体检测的效果。在固定划痕约束下，单目深度估计的方向性深度偏移达到高达32%的相对误差，并对单目3D物体检测产生一致影响。物理实验证实了向真实相机记录的迁移，诱导的深度偏移高于模型的自然预测基线。这些发现揭示了一个攻击面，其中看似无害的硬件缺陷充当潜在的场景触发的对抗机制，挑战了关于物理鲁棒性的假设，并激励了安全视觉系统的防御措施。