arXiv Computer Vision By Ahmed Abdelnaby, Mohamed Elmahallawy

Beyond Small Patches: Black-Box Detection and Purification of Diverse Backdoor Triggers

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The paper introduces TRIM, a black‑box defense for backdoor attacks in computer vision models. TRIM identifies and removes malicious trigger regions at inference time using region‑based segmentation, adaptive trigger discovery via inpainting and diffusion, and selective purification, without needing model internals, training data, or clean samples. Experiments on various datasets and trigger types show TRIM reduces attack success rates to as low as 1.16% while maintaining high clean accuracy.

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