Physical Backdoor: Towards Temperature-based Backdoor Attacks in the Physical World
Authors: Wen Yin, Jian Lou, Pan Zhou, Yulai Xie, Dan Feng, Yuhua Sun, Tailai Zhang, Lichao Sun

Backdoor attacks have been well-studied in visible light object detection (VLOD) in recent years. However VLOD can not effectively work in dark and temperature-sensitive scenarios. Instead thermal infrared object detection (TIOD) is the most accessible and practical in such environments. In this paper our team is the first to investigate the security vulnerabilities associated with TIOD in the context of backdoor attacks spanning both the digital and physical realms. We introduce two novel types of backdoor attacks on TIOD each offering unique capabilities: Object-affecting Attack and Range-affecting Attack. We conduct a comprehensive analysis of key factors influencing trigger design which include temperature size material and concealment. These factors especially temperature significantly impact the efficacy of backdoor attacks on TIOD. A thorough understanding of these factors will serve as a foundation for designing physical triggers and temperature controlling experiments. Our study includes extensive experiments conducted in both digital and physical environments. In the digital realm we evaluate our approach using benchmark datasets for TIOD achieving an Attack Success Rate (ASR) of up to 98.21%. In the physical realm we test our approach in two real-world settings: a traffic intersection and a parking lot using a thermal infrared camera. Here we attain an ASR of up to 98.38%.