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1. STATISTICAL MODELS FOR IMAGE STEGANOGRAPHY EXPLAINING AND REPLACING HEURISTICS

   Butor, Jan (May 2021, Binghamton University magazine)

   null (Ed.)

   The steganographic field is nowadays dominated by heuristic approaches for data hiding. While there exist a few model-based steganographic algorithms designed to minimize statistical detectability of the underlying model, many more algorithms based on costs of changing a specific pixel or a DCT coefficient have been over the last decade introduced. These costs are purely heuristic, as they are designed with feedback from detectors implemented as machine learning classifiers. For this reason, there is no apparent relation to statistical detectability, even though in practice they provide comparable security to model-based algorithms. Clearly, the security of such algorithms stands only on the assumption, that the detector used to assess the security, is the best one possible. Such assumption is of course completely unrealistic. Similarly, steganalysis is mainly implemented with empirical machine learning detectors, which use hand-crafted features computed from images or as deep learning detectors - convolutional neural networks. The biggest drawback of this approach is, that the steganalyst, even though having a very good detection power, has very little to no knowledge about what part of the image or the embedding algorithm contributes to the detection, because the detector is used as a black box. In this work, we will try to leave the heuristics behind and go towards statistical models. First, we introduce statistical models for current heuristic algorithms, which helps us understand and predict their security trends. Furthemore this allows us to improve the security of such algorithms. Next, we focus on steganalysis exploiting universal properties of JPEG images. Under certain realistic conditions, this leads to a very powerful attack against any steganography, because embedding even a very small secret message breaks the statistical model. Lastly, we show how we can improve security of JPEG compressed images through additional compression. 

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2. Please Tell Me More: Privacy Impact of Explainability through the Lens of Membership Inference Attack

   Liu, Han; Wu, Yuhao; Yu, Zhiyuan; Zhang, Ning (May 2024, 2024 IEEE Symposium on Security and Privacy (SP))

   Explainability is increasingly recognized as an enabling technology for the broader adoption of machine learning (ML), particularly for safety-critical applications. This has given rise to explainable ML, which seeks to enhance the explainability of neural networks through the use of explanators. Yet, the pursuit for better explainability inadvertently leads to increased security and privacy risks. While there has been considerable research into the security risks of explainable ML, its potential privacy risks remain under-explored. To bridge this gap, we present a systematic study of privacy risks in explainable ML through the lens of membership inference. Building on the observation that, besides the accuracy of the model, robustness also exhibits observable differences among member samples and non-member samples, we develop a new membership inference attack. This attack extracts additional membership features from changes in model confidence under different levels of perturbations guided by the importance highlighted by the attribution maps in the explanators. Intuitively, perturbing important features generally results in a bigger loss in confidence for member samples. Using the member-non-member differences in both model performance and robustness, an attack model is trained to distinguish the membership. We evaluated our approach with seven popular explanators across various benchmark models and datasets. Our attack demonstrates there is non-trivial privacy leakage in current explainable ML methods. Furthermore, such leakage issue persists even if the attacker lacks the knowledge of training datasets or target model architectures. Lastly, we also found existing model and output-based defense mechanisms are not effective in mitigating this new attack. 

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3. PA-JJAMA: An LLM Based Intrusion Detection System for CAN Bus Networks

   https://doi.org/10.1109/MASS66014.2025.00111  

   Quintano, Joshua; Qiang, Yao; Fu, Huirong (October 2025, IEEE)

   Recent studies have demonstrated significant success in detecting attacks on the Controller Area Network (CAN) bus network using machine learning and deep learning models, including convolutional neural networks and transformer-based architectures. Building on this foundation, our work investigates the use of large language models (LLMs) not only for intrusion detection but also for providing interpretable explanations of their decisions. We fine-tuned three LLMs, i.e., SecureBERT, LLaMA-2, and LLaMA-3, for intrusion detection on CAN bus data. Among them, LLaMA-3 delivered the best results, achieving SOTA performance on the Car-Hacking dataset. Beyond attack classification, we evaluated LLaMA-3’s ability to generate reasoning for its decisions through zero-shot prompting. The model successfully articulated its rationale, particularly for Denial-of- Service (DoS) attacks, demonstrating strong potential for explainability in intrusion detection systems. These findings highlight the potential of LLMs to serve as a highly accurate intrusion detection system while simultaneously providing interpretable explanations, thereby enhancing the investigative capabilities of cybersecurity professionals. 

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4. Assessing the Local Interpretability of Machine Learning Models.

   Slack, D.; Friedler, S.A.; Roy, C.D.; Scheidegger, C. (January 2019, NeurIPS Workshop on Human-Centric Machine Learning (HCML))

   The increasing adoption of machine learning tools has led to calls for accountability via model interpretability. But what does it mean for a machine learning model to be interpretable by humans, and how can this be assessed? We focus on two definitions of interpretability that have been introduced in the machine learning literature: simulatability (a user's ability to run a model on a given input) and "what if" local explainability (a user's ability to correctly determine a model's prediction under local changes to the input, given knowledge of the model's original prediction). Through a user study with 1,000 participants, we test whether humans perform well on tasks that mimic the definitions of simulatability and "what if" local explainability on models that are typically considered locally interpretable. To track the relative interpretability of models, we employ a simple metric, the runtime operation count on the simulatability task. We find evidence that as the number of operations increases, participant accuracy on the local interpretability tasks decreases. In addition, this evidence is consistent with the common intuition that decision trees and logistic regression models are interpretable and are more interpretable than neural networks. 

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5. A Cloud 3D Dataset and Application-Specific Learned Image Compression in Cloud 3D

   Liu, Tianyi; He, Sen; Jayakumar, Vinodh K; Wang, Wei (October 2022, European Conference on Computer Vision (ECCV))

   In Cloud 3D, such as Cloud Gaming and Cloud Virtual Reality (VR), image frames are rendered and compressed (encoded) in the cloud, and sent to the clients for users to view. For low latency and high image quality, fast, high compression rate, and high-quality image compression techniques are preferable. This paper explores computation time reduction techniques for learned image compression to make it more suitable for cloud 3D. More specifically, we employed slim (low-complexity) and application-specific AI models to reduce the computation time without degrading image quality. Our approach is based on two key insights: (1) as the frames generated by a 3D application are highly homogeneous, application-specific compression models can improve the rate-distortion performance over a general model; (2) many computer-generated frames from 3D applications are less complex than natural photos, which makes it feasible to reduce the model complexity to accelerate compression computation. We evaluated our models on six gaming image datasets. The results show that our approach has similar rate-distortion performance as a state-of-the-art learned image compression algorithm, while obtaining about 5x to 9x speedup and reducing the compression time to be less than 1 s (0.74s), bringing learned image compression closer to being viable for cloud 3D. Code is available at https://github.com/cloud-graphics-rendering/AppSpecificLIC. 

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