深度神经网络已被证明容易受到对抗图像的影响。常规攻击努力争取严格限制扰动的不可分割的对抗图像。最近，研究人员已采取行动探索可区分但非奇异的对抗图像，并证明色彩转化攻击是有效的。在这项工作中，我们提出了对抗颜色过滤器（ADVCF），这是一种新颖的颜色转换攻击，在简单颜色滤波器的参数空间中通过梯度信息进行了优化。特别是，明确指定了我们的颜色滤波器空间，以便从攻击和防御角度来对对抗性色转换进行系统的鲁棒性分析。相反，由于缺乏这种明确的空间，现有的颜色转换攻击并不能为系统分析提供机会。我们通过用户研究进一步进行了对成功率和图像可接受性的不同颜色转化攻击之间的广泛比较。其他结果为在另外三个视觉任务中针对ADVCF的模型鲁棒性提供了有趣的新见解。我们还强调了ADVCF的人类解剖性，该advcf在实际使用方案中有希望，并显示出比对图像可接受性和效率的最新人解释的色彩转化攻击的优越性。

Although deep neural networks (DNNs) have achieved great success in many tasks, they can often be fooled by adversarial examples that are generated by adding small but purposeful distortions to natural examples. Previous studies to defend against adversarial examples mostly focused on refining the DNN models, but have either shown limited success or required expensive computation. We propose a new strategy, feature squeezing, that can be used to harden DNN models by detecting adversarial examples. Feature squeezing reduces the search space available to an adversary by coalescing samples that correspond to many different feature vectors in the original space into a single sample. By comparing a DNN model's prediction on the original input with that on squeezed inputs, feature squeezing detects adversarial examples with high accuracy and few false positives.This paper explores two feature squeezing methods: reducing the color bit depth of each pixel and spatial smoothing. These simple strategies are inexpensive and complementary to other defenses, and can be combined in a joint detection framework to achieve high detection rates against state-of-the-art attacks.

The authors thank Nicholas Carlini (UC Berkeley) and Dimitris Tsipras (MIT) for feedback to improve the survey quality. We also acknowledge X. Huang (Uni. Liverpool), K. R. Reddy (IISC), E. Valle (UNICAMP), Y. Yoo (CLAIR) and others for providing pointers to make the survey more comprehensive.

已知深度神经网络（DNN）容易受到用不可察觉的扰动制作的对抗性示例的影响，即，输入图像的微小变化会引起错误的分类，从而威胁着基于深度学习的部署系统的可靠性。经常采用对抗训练（AT）来通过训练损坏和干净的数据的混合物来提高DNN的鲁棒性。但是，大多数基于AT的方法在处理\ textit {转移的对抗示例}方面是无效的，这些方法是生成以欺骗各种防御模型的生成的，因此无法满足现实情况下提出的概括要求。此外，对抗性训练一般的国防模型不能对具有扰动的输入产生可解释的预测，而不同的领域专家则需要一个高度可解释的强大模型才能了解DNN的行为。在这项工作中，我们提出了一种基于Jacobian规范和选择性输入梯度正则化（J-SIGR）的方法，该方法通过Jacobian归一化提出了线性化的鲁棒性，还将基于扰动的显着性图正规化，以模仿模型的可解释预测。因此，我们既可以提高DNN的防御能力和高解释性。最后，我们评估了跨不同体系结构的方法，以针对强大的对抗性攻击。实验表明，提出的J-Sigr赋予了针对转移的对抗攻击的鲁棒性，我们还表明，来自神经网络的预测易于解释。

Deep neural networks (DNNs) are one of the most prominent technologies of our time, as they achieve state-of-the-art performance in many machine learning tasks, including but not limited to image classification, text mining, and speech processing. However, recent research on DNNs has indicated ever-increasing concern on the robustness to adversarial examples, especially for security-critical tasks such as traffic sign identification for autonomous driving. Studies have unveiled the vulnerability of a well-trained DNN by demonstrating the ability of generating barely noticeable (to both human and machines) adversarial images that lead to misclassification. Furthermore, researchers have shown that these adversarial images are highly transferable by simply training and attacking a substitute model built upon the target model, known as a black-box attack to DNNs.Similar to the setting of training substitute models, in this paper we propose an effective black-box attack that also only has access to the input (images) and the output (confidence scores) of a targeted DNN. However, different from leveraging attack transferability from substitute models, we propose zeroth order optimization (ZOO) based attacks to directly estimate the gradients of the targeted DNN for generating adversarial examples. We use zeroth order stochastic coordinate descent along with dimension reduction, hierarchical attack and importance sampling techniques to * Pin-Yu Chen and Huan Zhang contribute equally to this work.

With rapid progress and significant successes in a wide spectrum of applications, deep learning is being applied in many safety-critical environments. However, deep neural networks have been recently found vulnerable to well-designed input samples, called adversarial examples. Adversarial perturbations are imperceptible to human but can easily fool deep neural networks in the testing/deploying stage. The vulnerability to adversarial examples becomes one of the major risks for applying deep neural networks in safety-critical environments. Therefore, attacks and defenses on adversarial examples draw great attention. In this paper, we review recent findings on adversarial examples for deep neural networks, summarize the methods for generating adversarial examples, and propose a taxonomy of these methods. Under the taxonomy, applications for adversarial examples are investigated. We further elaborate on countermeasures for adversarial examples. In addition, three major challenges in adversarial examples and the potential solutions are discussed.

发言人识别系统（SRSS）最近被证明容易受到对抗攻击的影响，从而引发了重大的安全问题。在这项工作中，我们系统地研究了基于确保SRSS的基于对抗性训练的防御。根据SRSS的特征，我们提出了22种不同的转换，并使用扬声器识别的7种最新有前途的对抗攻击（4个白盒和3个Black-Box）对其进行了彻底评估。仔细考虑了国防评估中的最佳实践，我们分析了转换的强度以承受适应性攻击。我们还评估并理解它们与对抗训练相结合的自适应攻击的有效性。我们的研究提供了许多有用的见解和发现，其中许多与图像和语音识别域中的结论是新的或不一致的，例如，可变和恒定的比特率语音压缩具有不同的性能，并且某些不可差的转换仍然有效地抗衡。当前有希望的逃避技术通常在图像域中很好地工作。我们证明，与完整的白色盒子设置中的唯一对抗性训练相比，提出的新型功能级转换与对抗训练相比是相当有效的，例如，将准确性提高了13.62％，而攻击成本则达到了两个数量级，而其他攻击成本则增加了。转型不一定会提高整体防御能力。这项工作进一步阐明了该领域的研究方向。我们还发布了我们的评估平台SpeakerGuard，以促进进一步的研究。

深度神经网络（DNNS）在各种方案中对对抗数据敏感，包括黑框方案，在该方案中，攻击者只允许查询训练有素的模型并接收输出。现有的黑框方法用于创建对抗性实例的方法是昂贵的，通常使用梯度估计或培训替换网络。本文介绍了\ textit {Attackar}，这是一种基于分数的进化，黑框攻击。 Attackar是基于一个新的目标函数，可用于无梯度优化问题。攻击仅需要访问分类器的输出徽标，因此不受梯度掩蔽的影响。不需要其他信息，使我们的方法更适合现实生活中的情况。我们使用三个基准数据集（MNIST，CIFAR10和Imagenet）使用三种不同的最先进模型（Inception-V3，Resnet-50和VGG-16-BN）测试其性能。此外，我们评估了Attackar在非分辨率转换防御和最先进的强大模型上的性能。我们的结果表明，在准确性得分和查询效率方面，攻击性的表现出色。

深度神经网络容易受到来自对抗性投入的攻击，并且最近，特洛伊木马误解或劫持模型的决定。我们通过探索有界抗逆性示例空间和生成的对抗网络内的自然输入空间来揭示有界面的对抗性实例 - 通用自然主义侵害贴片的兴趣类 - 我们呼叫TNT。现在，一个对手可以用一个自然主义的补丁来手臂自己，不太恶意，身体上可实现，高效 - 实现高攻击成功率和普遍性。 TNT是普遍的，因为在场景中的TNT中捕获的任何输入图像都将：i）误导网络（未确定的攻击）;或ii）迫使网络进行恶意决定（有针对性的攻击）。现在，有趣的是，一个对抗性补丁攻击者有可能发挥更大的控制水平 - 选择一个独立，自然的贴片的能力，与被限制为嘈杂的扰动的触发器 - 到目前为止只有可能与特洛伊木马攻击方法有可能干扰模型建设过程，以嵌入风险发现的后门;但是，仍然意识到在物理世界中部署的补丁。通过对大型视觉分类任务的广泛实验，想象成在其整个验证集50,000张图像中进行评估，我们展示了TNT的现实威胁和攻击的稳健性。我们展示了攻击的概括，以创建比现有最先进的方法实现更高攻击成功率的补丁。我们的结果表明，攻击对不同的视觉分类任务（CIFAR-10，GTSRB，PUBFIG）和多个最先进的深神经网络，如WieredEnet50，Inception-V3和VGG-16。

Video classification systems are vulnerable to adversarial attacks, which can create severe security problems in video verification. Current black-box attacks need a large number of queries to succeed, resulting in high computational overhead in the process of attack. On the other hand, attacks with restricted perturbations are ineffective against defenses such as denoising or adversarial training. In this paper, we focus on unrestricted perturbations and propose StyleFool, a black-box video adversarial attack via style transfer to fool the video classification system. StyleFool first utilizes color theme proximity to select the best style image, which helps avoid unnatural details in the stylized videos. Meanwhile, the target class confidence is additionally considered in targeted attacks to influence the output distribution of the classifier by moving the stylized video closer to or even across the decision boundary. A gradient-free method is then employed to further optimize the adversarial perturbations. We carry out extensive experiments to evaluate StyleFool on two standard datasets, UCF-101 and HMDB-51. The experimental results demonstrate that StyleFool outperforms the state-of-the-art adversarial attacks in terms of both the number of queries and the robustness against existing defenses. Moreover, 50% of the stylized videos in untargeted attacks do not need any query since they can already fool the video classification model. Furthermore, we evaluate the indistinguishability through a user study to show that the adversarial samples of StyleFool look imperceptible to human eyes, despite unrestricted perturbations.

Convolutional neural networks have demonstrated high accuracy on various tasks in recent years. However, they are extremely vulnerable to adversarial examples. For example, imperceptible perturbations added to clean images can cause convolutional neural networks to fail. In this paper, we propose to utilize randomization at inference time to mitigate adversarial effects. Specifically, we use two randomization operations: random resizing, which resizes the input images to a random size, and random padding, which pads zeros around the input images in a random manner. Extensive experiments demonstrate that the proposed randomization method is very effective at defending against both single-step and iterative attacks. Our method provides the following advantages: 1) no additional training or fine-tuning, 2) very few additional computations, 3) compatible with other adversarial defense methods. By combining the proposed randomization method with an adversarially trained model, it achieves a normalized score of 0.924 (ranked No.2 among 107 defense teams) in the NIPS 2017 adversarial examples defense challenge, which is far better than using adversarial training alone with a normalized score of 0.773 (ranked No.56). The code is public available at https: //github.com/cihangxie/NIPS2017_adv_challenge_defense.

许多最先进的ML模型在各种任务中具有优于图像分类的人类。具有如此出色的性能，ML模型今天被广泛使用。然而，存在对抗性攻击和数据中毒攻击的真正符合ML模型的稳健性。例如，Engstrom等人。证明了最先进的图像分类器可以容易地被任意图像上的小旋转欺骗。由于ML系统越来越纳入安全性和安全敏感的应用，对抗攻击和数据中毒攻击构成了相当大的威胁。本章侧重于ML安全的两个广泛和重要的领域：对抗攻击和数据中毒攻击。

共同突出的对象检测（Cosod）最近实现了重大进展，并在检索相关任务中发挥了关键作用。但是，它不可避免地构成了完全新的安全问题，即，高度个人和敏感的内容可能会通过强大的COSOD方法提取。在本文中，我们从对抗性攻击的角度解决了这个问题，并确定了一种小说任务：对抗的共同显着性攻击。特别地，给定从包含某种常见和突出对象的一组图像中选择的图像，我们的目标是生成可能误导Cosod方法以预测不正确的共突变区域的侵略性版本。注意，与分类的一般白盒对抗攻击相比，这项新任务面临两种额外的挑战：（1）由于本集团中图像的不同外观，成功率低; （2）Cosod方法的低可转换性由于Cosod管道之间的差异相当差异。为了解决这些挑战，我们提出了第一个黑匣子联合对抗的暴露和噪声攻击（JADENA），在那里我们共同和本地调整图像的曝光和添加剂扰动，根据新设计的高特征级对比度敏感损失功能。我们的方法，没有关于最先进的Cosod方法的任何信息，导致各种共同显着性检测数据集的显着性能下降，并使共同突出的物体无法检测到。这在适当地确保目前在互联网上共享的大量个人照片中可以具有很强的实际效益。此外，我们的方法是用于评估Cosod方法的稳健性的指标的潜力。

基于深的神经网络（DNNS）基于合成孔径雷达（SAR）自动靶标识别（ATR）系统已显示出非常容易受到故意设计但几乎无法察觉的对抗扰动的影响，但是当添加到靶向物体中时，DNN推断可能会偏差。在将DNN应用于高级SAR ATR应用时，这会导致严重的安全问题。因此，增强DNN的对抗性鲁棒性对于对现代现实世界中的SAR ATR系统实施DNN至关重要。本文旨在构建更健壮的DNN基于DNN的SAR ATR模型，探讨了SAR成像过程的领域知识，并提出了一种新型的散射模型引导的对抗攻击（SMGAA）算法，该算法可以以电磁散射响应的形式产生对抗性扰动（称为对抗散射器） ）。提出的SMGAA由两个部分组成：1）参数散射模型和相应的成像方法以及2）基于自定义的基于梯度的优化算法。首先，我们介绍了有效的归因散射中心模型（ASCM）和一种通用成像方法，以描述SAR成像过程中典型几何结构的散射行为。通过进一步制定几种策略来考虑SAR目标图像的领域知识并放松贪婪的搜索程序，建议的方法不需要经过审慎的态度，但是可以有效地找到有效的ASCM参数来欺骗SAR分类器并促进SAR分类器并促进强大的模型训练。对MSTAR数据集的全面评估表明，SMGAA产生的对抗散射器对SAR处理链中的扰动和转换比当前研究的攻击更为强大，并且有效地构建了针对恶意散射器的防御模型。

Deep neural networks are vulnerable to adversarial examples, which poses security concerns on these algorithms due to the potentially severe consequences. Adversarial attacks serve as an important surrogate to evaluate the robustness of deep learning models before they are deployed. However, most of existing adversarial attacks can only fool a black-box model with a low success rate. To address this issue, we propose a broad class of momentum-based iterative algorithms to boost adversarial attacks. By integrating the momentum term into the iterative process for attacks, our methods can stabilize update directions and escape from poor local maxima during the iterations, resulting in more transferable adversarial examples. To further improve the success rates for black-box attacks, we apply momentum iterative algorithms to an ensemble of models, and show that the adversarially trained models with a strong defense ability are also vulnerable to our black-box attacks. We hope that the proposed methods will serve as a benchmark for evaluating the robustness of various deep models and defense methods. With this method, we won the first places in NIPS 2017 Non-targeted Adversarial Attack and Targeted Adversarial Attack competitions.

We propose the Square Attack, a score-based black-box l2and l∞-adversarial attack that does not rely on local gradient information and thus is not affected by gradient masking. Square Attack is based on a randomized search scheme which selects localized squareshaped updates at random positions so that at each iteration the perturbation is situated approximately at the boundary of the feasible set. Our method is significantly more query efficient and achieves a higher success rate compared to the state-of-the-art methods, especially in the untargeted setting. In particular, on ImageNet we improve the average query efficiency in the untargeted setting for various deep networks by a factor of at least 1.8 and up to 3 compared to the recent state-ofthe-art l∞-attack of Al-Dujaili & OReilly (2020). Moreover, although our attack is black-box, it can also outperform gradient-based white-box attacks on the standard benchmarks achieving a new state-of-the-art in terms of the success rate. The code of our attack is available at https://github.com/max-andr/square-attack.

Though CNNs have achieved the state-of-the-art performance on various vision tasks, they are vulnerable to adversarial examples -crafted by adding human-imperceptible perturbations to clean images. However, most of the existing adversarial attacks only achieve relatively low success rates under the challenging black-box setting, where the attackers have no knowledge of the model structure and parameters. To this end, we propose to improve the transferability of adversarial examples by creating diverse input patterns. Instead of only using the original images to generate adversarial examples, our method applies random transformations to the input images at each iteration. Extensive experiments on ImageNet show that the proposed attack method can generate adversarial examples that transfer much better to different networks than existing baselines. By evaluating our method against top defense solutions and official baselines from NIPS 2017 adversarial competition, the enhanced attack reaches an average success rate of 73.0%, which outperforms the top-1 attack submission in the NIPS competition by a large margin of 6.6%. We hope that our proposed attack strategy can serve as a strong benchmark baseline for evaluating the robustness of networks to adversaries and the effectiveness of different defense methods in the future. Code is available at https: //github.com/cihangxie/DI-2-FGSM .

基于转移的对手示例是最重要的黑匣子攻击类别之一。然而，在对抗性扰动的可转移性和难以察觉之间存在权衡。在此方向上的事先工作经常需要固定但大量的$ \ ell_p $ -norm扰动预算，达到良好的转移成功率，导致可察觉的对抗扰动。另一方面，目前的大多数旨在产生语义保留扰动的难以限制的对抗攻击患有对目标模型的可转移性较弱。在这项工作中，我们提出了一个几何形象感知框架，以产生具有最小变化的可转移的对抗性示例。类似于在统计机器学习中的模型选择，我们利用验证模型为$ \ ell _ {\ infty} $ - norm和不受限制的威胁模型中选择每个图像的最佳扰动预算。广泛的实验验证了我们对平衡令人难以置信的难以察觉和可转移性的框架的有效性。方法论是我们进入CVPR'21安全性AI挑战者的基础：对想象成的不受限制的对抗攻击，其中我们将第1位排名第1,559支队伍，并在决赛方面超过了亚军提交的提交4.59％和23.91％分别和平均图像质量水平。代码可在https://github.com/equationliu/ga-attack获得。

基于深度神经网络（DNN）的智能信息（IOT）系统已被广泛部署在现实世界中。然而，发现DNNS易受对抗性示例的影响，这提高了人们对智能物联网系统的可靠性和安全性的担忧。测试和评估IOT系统的稳健性成为必要和必要。最近已经提出了各种攻击和策略，但效率问题仍未纠正。现有方法是计算地广泛或耗时，这在实践中不适用。在本文中，我们提出了一种称为攻击启发GaN（AI-GaN）的新框架，在有条件地产生对抗性实例。曾经接受过培训，可以有效地给予对抗扰动的输入图像和目标类。我们在白盒设置的不同数据集中应用AI-GaN，黑匣子设置和由最先进的防御保护的目标模型。通过广泛的实验，AI-GaN实现了高攻击成功率，优于现有方法，并显着降低了生成时间。此外，首次，AI-GaN成功地缩放到复杂的数据集。 Cifar-100和Imagenet，所有课程中的成功率约为90美元。

基于深度学习的图像识别系统已广泛部署在当今世界的移动设备上。然而，在最近的研究中，深入学习模型被证明易受对抗的例子。一种逆势例的一个变种，称为对抗性补丁，由于其强烈的攻击能力而引起了研究人员的注意。虽然对抗性补丁实现了高攻击成功率，但由于补丁和原始图像之间的视觉不一致，它们很容易被检测到。此外，它通常需要对文献中的对抗斑块产生的大量数据，这是计算昂贵且耗时的。为了解决这些挑战，我们提出一种方法来产生具有一个单一图像的不起眼的对抗性斑块。在我们的方法中，我们首先通过利用多尺度发生器和鉴别器来决定基于受害者模型的感知敏感性的补丁位置，然后以粗糙的方式产生对抗性斑块。鼓励修补程序与具有对抗性训练的背景图像一致，同时保留强烈的攻击能力。我们的方法显示了白盒设置中的强烈攻击能力以及通过对具有不同架构和培训方法的各种型号的广泛实验，通过广泛的实验进行黑盒设置的优异转移性。与其他对抗贴片相比，我们的对抗斑块具有最大忽略的风险，并且可以避免人类观察，这是由显着性图和用户评估结果的插图支持的人类观察。最后，我们表明我们的对抗性补丁可以应用于物理世界。