论文标题
利用删除的表示以改善低数据下的基于视觉的击键推理攻击
Leveraging Disentangled Representations to Improve Vision-Based Keystroke Inference Attacks Under Low Data
论文作者
论文摘要
击键推理攻击是侧通道攻击的一种形式,在该攻击者中,攻击者在将信息输入某些显示器中(例如,在发送短信或输入她的PIN)时,利用各种技术来恢复用户的击键。通常,这些攻击利用机器学习方法,但是评估威胁空间的现实主义却落后于机器学习进步的步伐,该进步是由于策划大型现实生活数据集所面临的挑战。我们旨在通过引入视频域适应技术来克服有限数量的真实数据的挑战,该技术能够通过有监督的分离学习来利用合成数据。具体而言,对于给定的域,我们将观察到的数据分解为两个变化因素:样式和内容。这样做提供了四个学识渊博的表示:现实生活样式,综合样式,现实生活中的内容和合成内容。然后,我们将它们合并为跨域样式配对的所有组合组合的特征表示,并在这些组合表示形式上训练模型,以将给定数据标记的内容(即标签)分类为另一个域的样式。我们使用各种指标对现实数据进行评估方法,以量化攻击者能够恢复的信息量。我们表明,我们的方法可以防止我们的模型过度拟合到小型现实生活训练集,这表明我们的方法是一种有效的数据增强形式,从而使击键推理攻击更加实用。
Keystroke inference attacks are a form of side-channel attacks in which an attacker leverages various techniques to recover a user's keystrokes as she inputs information into some display (e.g., while sending a text message or entering her pin). Typically, these attacks leverage machine learning approaches, but assessing the realism of the threat space has lagged behind the pace of machine learning advancements, due in-part, to the challenges in curating large real-life datasets. We aim to overcome the challenge of having limited number of real data by introducing a video domain adaptation technique that is able to leverage synthetic data through supervised disentangled learning. Specifically, for a given domain, we decompose the observed data into two factors of variation: Style and Content. Doing so provides four learned representations: real-life style, synthetic style, real-life content and synthetic content. Then, we combine them into feature representations from all combinations of style-content pairings across domains, and train a model on these combined representations to classify the content (i.e., labels) of a given datapoint in the style of another domain. We evaluate our method on real-life data using a variety of metrics to quantify the amount of information an attacker is able to recover. We show that our method prevents our model from overfitting to a small real-life training set, indicating that our method is an effective form of data augmentation, thereby making keystroke inference attacks more practical.