ZOO: Zeroth Order Optimization based Black-box Attacks to Deep Neural Networks

ZOO is a zeroth order optimization based attack to attack deep neural networks (DNNs). We propose an effective black-box attack that only requires access to the input (images) and the output (confidence scores) of a targeted DNN. We formularize the attack as an optimization problem (similar as Carlini and Wagner's attack), and propose a new loss function suitable for the black-box setting. We use zeroth order stochastic coordinate descent to optimize on the target DNN directly, along with dimension reduction, hierarchical attack and importance sampling techniques to make the attack efficient. No transferability or substitute model is required.

There are two variants of ZOO, ZOO-ADAM and ZOO-Newton, corresponding to different solvers (ADAM and Newton) to find the best coordinate update. In practice ZOO-ADAM usually works better with fine-tuned parameters, but ZOO-Newton is more stable when close to the optimal solution.

The experiment code is based on Carlini and Wagner's L2 attack, with zeroth order optimizer added in l2_attack_black.py. The inception model is updated to a new version (inception_v3_2016_08_28.tar.gz), and an unified interface test_all.py is added.

For more details, please see our paper:

ZOO: Zeroth Order Optimization based Black-box Attacks to Deep Neural Networks without Training Substitute Models by Pin-Yu Chen*, Huan Zhang*, Yash Sharma, Jinfeng Yi, Cho-Jui Hsieh

* Equal contribution

Setup and train models

The code is tested with python3 and TensorFlow v1.2 and v1.3. The following packages are required:

sudo apt-get install python3-pip
sudo pip3 install --upgrade pip
sudo pip3 install pillow scipy numpy tensorflow-gpu keras h5py numba

Prepare the MNIST and CIFAR-10 data and models for attack:

python3 train_models.py

To download the inception model:

python3 setup_inception.py

To prepare the ImageNet dataset, download and unzip the following archive:

ImageNet Test Set

and put the imgs folder in ../imagenetdata. This path can be changed in setup_inception.py.

Run attacks

An unified attack interface, test_all.py is provided. Run python3 test_all.py -h to get a list of arguments and help.

The following are some examples of attacks:

Run ZOO black-box targeted attack, on the mnist dataset with 200 images, with ZOO-ADAM solver, search for best regularization constant for 9 iterations, and save attack images to folder black_results. To run on the CIFAR-10 dataset, replace 'mnist' with 'cifar10'.

python3 test_all.py -a black -d mnist -n 200 --solver adam -b 9 -s "black_results"

Run Carlini and Wagner's white-box targeted attack, on the mnist dataset with 200 images, using the Z (logits) value in objective (only available in white-box setting), search for best regularization constant for 9 iterations, and save attack images to folder white_results.

python3 test_all.py -a white -d mnist -n 200 --use_zvalue -b 9 -s "white_results"

Run ZOO black-box untargeted attack, on the imagenet dataset with 150 images, with ZOO-ADAM solver, do not binary search the regularization parameter (i.e., search only 1 time), and set the initial regularization parameter to a fixed value (10.0). Use attack-space dimension reduction with image resizing, and reset ADAM states when the first attack is found. Run a maximum of 1500 iterations, and print out loss every 10 iterations. Save attack images to folder imagenet_untargeted.

python3 test_all.py --untargeted -a black -d imagenet -n 150 --solver adam -b 1 -c 10.0 --use_resize --reset_adam -m 1500 -p 10 -s "imagenet_untargeted"

Run ZOO black-box targeted attack, on the imagenet dataset, with the 69th image only. Set the regularization parameter to 10.0 and do not binary search. Use attack-space dimension reduction and hierarchical attack with image resizing, and reset ADAM states when the first attack is found. Run a maximum of 20000 iterations, and print out loss every 10 iterations. Save attack images to folder imagenet_all_tricks_img69.

python3 test_all.py -a black --solver adam -d imagenet -f 69 -n 1 -c 10.0 --use_resize --reset_adam -m 20000 -p 10 -s "imagenet_all_tricks_img69"

Importance sampling is on by default for ImageNet data, and can be turned off by --uniform option. To change the hierarchical attack dimension scheduling, change l2_attack_black.py, near line 580.