  Multiple different approaches of generating adversarial examples have been
proposed to attack deep neural networks. These approaches involve either
directly computing gradients with respect to the image pixels, or directly
solving an optimization on the image pixels. In this work, we present a
fundamentally new method for generating adversarial examples that is fast to
execute and provides exceptional diversity of output. We efficiently train
feed-forward neural networks in a self-supervised manner to generate
adversarial examples against a target network or set of networks. We call such
a network an Adversarial Transformation Network (ATN). ATNs are trained to
generate adversarial examples that minimally modify the classifier's outputs
given the original input, while constraining the new classification to match an
adversarial target class. We present methods to train ATNs and analyze their
effectiveness targeting a variety of MNIST classifiers as well as the latest
state-of-the-art ImageNet classifier Inception ResNet v2.
