Nowadays, convolutional neural network (CNN) based steganalysis methods achieved great performance. While those methods are also facing security problems. In this paper, we proposed an attack scheme aiming at CNN based steganalyzer including two different attack methods 1) the LSB-Jstego Gradient Based Attack; 2) LSB-Jstego Evolutionary Algorithms Based Attack. The experiment results show that the attack strategies could achieve 96.02% and 90.25% success ratio separately on the target CNN. The proposed attack scheme is an effective way to fool the CNN based steganalyzer and in addition demonstrates the vulnerability of the neural networks in steganalysis. © 2018, Springer Science+Business Media, LLC, part of Springer Nature.

In this paper, a low distortion reversible database watermarking method based on histogram gap is proposed in view of the large gap in histogram of database integer data. By using the method, the tolerance of the attribute column containing all integer data is firstly calculated and the prediction error is obtained according to the tolerance. Then according to the watermark bits to be embedded, the database tuples will be randomly grouped and the histogram can be constructed by using the prediction error. Finally, the histogram correction rule is used to find the histogram peak bin, the number of consecutive non-zero prediction errors on the left and right sides of the peak is obtained, and the histogram shift is performed on the side with a smaller number of non-zero prediction errors, and then the watermark embedding will be realized. The results of the experiments based on the published dataset of FCTD (Forest Cover Type Dataset) show that compared with the existing GAHSW which also considers distortion, the proposed method significantly reduces the number of histogram column shift while embedding the watermarks, greatly reduces the changes to the carrier data, and effectively reduces the database's data distortion caused by watermark embedding.

Existing algorithms experience difficulty resisting additive and subtractive attacks because the embedded watermarks are independent of the carrier programs. A dynamic software watermarking algorithm based on exception handling is proposed in this paper. The algorithm considers the fact that exception handling, which is difficult to remove, commonly exists in the programs to ensure the normal program operation. First, an exception type table is constructed, and the binary watermark to be embedded is mapped to a sequence of exception types by scrambling encoding. Second, corresponding trigger conditions and exception handlers are constructed, and watermark embeddable points are acquired in execution paths under secret inputs. Finally, the code segment of the constructed trigger conditions and exception handlers are inserted into the program with several meticulously designed identifiers. For watermark extraction, the triggered exception types can be obtained with the identifiers by executing the watermarked executable program under secret inputs. The mapping relationship between the exception type and watermark is utilized to decode the binary watermark. The algorithm analysis and experimental results show that the proposed algorithm can embed a watermark in the source code and extract it in an executable program. The algorithm demonstrates good performance against additive and subtractive attacks.

Due to the existence of multiple views in many real-world data sets, multi-view clustering is increasingly popular. Many approaches have been investigated, among which the subspace clustering methods finding the underlying subspaces of data have been developed recently. Although the subspace-based multi-view methods can achieve promising performance, the shared subspace information has not been fully utilized. To address this problem, a novel multi-view clustering model by simultaneously learning shared subspace and affinity matrix is proposed. In our method, a shared subspace is learned to preserve the effective consensus information of all views. Then, a subspace-based affinity matrix with adaptive neighbors is learned to assign the most suitable cluster to each data point. An iterative strategy is developed for solving this problem. Moreover, experiments on four benchmark data sets demonstrate that our algorithm outperforms other state-of-the-art algorithms.

Digital image watermarking used to be an important tool for copyright protection. However, as neural network-based watermark removal methods have been proposed in recent years, the embedded watermark is increasingly easy to be erased, which poses a great threat to copyright protection. To address this issue, we propose an adversarial visible watermark scheme, which combines the visible watermark with the adversarial perturbation. By attacking the watermark removal network, we maximize the resistance of visible watermark against removal while minimizing the visual distortion. To further improve the robustness against various transformations (e.g. cropping, JPEG compression), we employ the region of interest and random pre-processing to embed the adversarial visible watermark. The experimental results show that the proposed scheme can effectively resist the removal of watermarks on different datasets and network structures while having good transferability and robustness, which enables the watermark to continue to be an effective copyright protection method. © 2024 Elsevier Ltd

The increasing amount of graph-structured data catalyzes analytics over graph databases using semantic queries. Motivated by the ubiquity of commercial cloud platforms, data owners are willing to store their graph databases remotely. However, data privacy has emerged as a widespread concern since the cloud platforms are not fully trusted. One viable solution is to encrypt sensitive data before outsourcing, which inevitably hinders data retrieval. To enable queries over encrypted data, searchable symmetric encryption (SSE) has been introduced. Yet, the most well-studied class of SSE schemes focuses on retrieving textual files given keywords, which cannot be applied to graph databases directly. This paper extends our preliminary work (FC'17) and proposes GraphShield, a structured encryption scheme for graphs. Beyond shortest distance queries, GraphShield can support other classic graph-based queries (e.g., maximum flow) and more complicated analytics (e.g., PageRank). Technically, we incorporate a suite of (efficient) cryptographic primitives and tailor some extra secure protocols for facilitating graph analytics. Our scheme also allows updates on the encrypted graph with forward privacy guaranteed. We formalize the security model and prove the adaptive security with reasonable leakage. Finally, we implement our scheme on various real-world datasets, and the experiment results demonstrate its practicality and scalability.

Traditional steganography methods are usually designed on a lossless channel; thus, messages are often not extracted correctly from an image transmitted over a lossy channel that includes attacks such as scaling. To address this issue, in recent years, the field of robust steganography has emerged. In this paper, the process of image scaling by interpolation is first observed and serves as the basis for proposing the idea of inverse interpolation. Subsequently, the idea of constructing an inverse interpolation equation set is proposed to solve the problem of intersectional blocks during the inverse interpolation process. Then, the scaling factor's valid range of inverse interpolation is analyzed. Next, the inverse interpolation is successfully applied in robust image steganography. A method that combines antiscaling and antidetection is proposed. Afterward, actual tests on the top 9 mobile phone brands with 28 models and 2 social communication apps that are currently popular in China are done. The scaling factor's valid range of the proposed method is verified to match the actual lossy channel. The experimental results show that the proposed method achieves a reliable extraction of embedded messages for common interpolation scaling attacks while maintaining high statistical detection resistance.

Convolutional neural networks (CNN) is a popular architecture in machine learning for its predictive power, notably in computer vision and medical image analysis. Its great predictive power requires extensive computation, which encourages model owners to host the prediction service in a cloud platform. This article proposes a CNN prediction scheme that preserves privacy in the outsourced setting, i.e., the model-hosting server cannot learn the query, (intermediate) results, and the model. Similar to SecureML (S&P'17), a representative work that provides model privacy, we employ two non-colluding servers with secret sharing and triplet generation to minimize the usage of heavyweight cryptography. We made the following optimizations for both overall latency and accuracy. 1) We adopt asynchronous computation and SIMD for offline triplet generation and parallelizable online computation. 2) As MiniONN (CCS'17) and its improvement by the generic EzPC compiler (EuroS&P'19), we use a garbled circuit for the non-polynomial ReLU activation to keep the same accuracy as the underlying network (instead of approximating it in SecureML prediction). 3) For the pooling in CNN, we employ (linear) average-pooling, which achieves almost the same accuracy as the (non-linear, and hence less efficient) max-pooling exhibited by MiniONN and EzPC. Considering both offline and online costs, our experiments on the MNIST dataset show a latency reduction of 122 x, 14.63 x, and 36.69x compared to SecureML, MiniONN, and EzPC; and a reduction of communication costs by 1.09 x, 36.69 x, and 31.32 x, respectively. On the CIFAR dataset, our scheme achieves a lower latency by 7.14x and 3.48x and lower communication costs by 13.88x and 77.46x when compared with MiniONN and EzPC, respectively.

Since the performance of STC (Syndrome-Trellis Codes) is approaching the theoretical optimum in minimizing embedded distortion, STC-based adaptive steganography has become the focus of forward improvement and the difficulty of reverse analysis of steganography algorithms. At present, the researches on secret message extraction from STC-based adaptive steganography are mainly focused on the scenario where the secret message is plaintext and part of the plaintext format information is known, while it needs to be studied when these characteristics are unknown. Analogous to the "known-plaintext attack" in cryptanalysis, this manuscript proposes a steganographic key recovery algorithm under the condition of "known-message attack". Firstly, by studying the structure characteristics of STC parity-check matrix, the concept of basic row vector is proposed, and the problem of secret message extraction attack is transformed into the problem of solving the basic row vectors. Then, the existence of bit string with special structure in the differential sequences of stego sequences is proved. Finally, using the distribution characteristics of the special bit strings in the differential sequence, the problem of solving the basic row vectors is transformed into the problem of solving the simple linear equation system through the differential analysis, and good code judgment criteria is used to filter out the correct steganographic key. The research results of this manuscript can realize the secret message extraction attack when the secret message is ciphertext, which is expected to solve the application requirements of actual scenarios. At the same time, the experimental results also show that, based on the algorithm proposed in this manuscript, only a PC can be used to extract secret message from the common STC-based adaptive steganography algorithm. © 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.

To better solve the contradiction between the localization accuracy, localization coverage, and the location of anchor nodes in wireless sensor networks, a node localization algorithm for wireless sensor networks based on static anchor node location selection strategy is proposed in this paper. Firstly, collect the signal strength between wireless sensor network nodes, judge whether there is a connection between nodes according to the set signal strength threshold, and convert the node distribution diagram into the node connection relationship diagram, that is, the topology diagram. Then, the closeness centrality value of each node is calculated by using the closeness centrality algorithm, and the obtained closeness centrality values are sorted in descending order, the node with the largest closeness centrality value is the first anchor node, the closeness centrality values are traversed at equal intervals, and the optimal equal interval is selected by using the quick sort algorithm, and the selected nodes are used as the other anchor nodes. Finally, other unknown nodes in the network are located according to the location of anchor nodes. Simulation results show that the proposed algorithm is superior to the existing typical algorithms in localization accuracy and localization coverage. © 2022 The Author(s)