2026
Tight Robustness Certification Through the Convex Hull of ℓ₀ Attacks
AAAI 2026technical
Few-pixel attacks mislead a classifier by modifying a few pixels of an image. Their perturbation space is an ℓ₀-ball, which is not convex, unlike ℓₚ-balls for p ≥ 1. However, existing local robustness verifiers typically scale by relying on linear bound propagation, which captures convex perturbatio