  Infrared imaging systems have a vast array of potential applications in
pedestrian detection and autonomous driving, and their safety performance is of
great concern. However, few studies have explored the safety of infrared
imaging systems in real-world settings. Previous research has used physical
perturbations such as small bulbs and thermal "QR codes" to attack infrared
imaging detectors, but such methods are highly visible and lack stealthiness.
Other researchers have used hot and cold blocks to deceive infrared imaging
detectors, but this method is limited in its ability to execute attacks from
various angles. To address these shortcomings, we propose a novel physical
attack called adversarial infrared blocks (AdvIB). By optimizing the physical
parameters of the adversarial infrared blocks, this method can execute a
stealthy black-box attack on thermal imaging system from various angles. We
evaluate the proposed method based on its effectiveness, stealthiness, and
robustness. Our physical tests show that the proposed method achieves a success
rate of over 80% under most distance and angle conditions, validating its
effectiveness. For stealthiness, our method involves attaching the adversarial
infrared block to the inside of clothing, enhancing its stealthiness.
Additionally, we test the proposed method on advanced detectors, and
experimental results demonstrate an average attack success rate of 51.2%,
proving its robustness. Overall, our proposed AdvIB method offers a promising
avenue for conducting stealthy, effective and robust black-box attacks on
thermal imaging system, with potential implications for real-world safety and
security applications.
