Adversarial perturbations are critical for certifying the robustness of deep
learning models. A universal adversarial perturbation (UAP) can simultaneously
attack multiple images, and thus offers a more unified threat model, obviating
an image-wise attack algorithm. However, the existing UAP generator is
underdeveloped when images are drawn from different image sources (e.g., with
different image resolutions). Towards an authentic universality across image
sources, we take a novel view of UAP generation as a customized instance of
few-shot learning, which leverages bilevel optimization and
learning-to-optimize (L2O) techniques for UAP generation with improved attack
success rate (ASR). We begin by considering the popular model agnostic
meta-learning (MAML) framework to meta-learn a UAP generator. However, we see
that the MAML framework does not directly offer the universal attack across
image sources, requiring us to integrate it with another meta-learning
framework of L2O. The resulting scheme for meta-learning a UAP generator (i)
has better performance (50% higher ASR) than baselines such as Projected
Gradient Descent, (ii) has better performance (37% faster) than the vanilla L2O
and MAML frameworks (when applicable), and (iii) is able to simultaneously
handle UAP generation for different victim models and image data sources.