Nowadays, there are plenty of works introducing convolutional neural networks (CNNs) to the steganalysis and exceeding conventional steganalysis algorithms. These works have shown the improving potential of deep learning in information hiding domain. There are also several works based on deep learning to do image steganography, but these works still have problems in capacity, invisibility and security. In this paper, we propose a novel CNN architecture named as ISGAN to conceal a secret gray image into a color cover image on the sender side and exactly extract the secret image out on the receiver side. There are three contributions in our work: (i) we improve the invisibility by hiding the secret image only in the Y channel of the cover image; (ii) We introduce the generative adversarial networks to strengthen the security by minimizing the divergence between the empirical probability distributions of stego images and natural images. (iii) In order to associate with the human visual system better, we construct a mixed loss function which is more appropriate for steganography to generate more realistic stego images and reveal out more better secret images. Experiment results show that ISGAN can achieve start-of-art performances on LFW, PASCAL-VOC12 and ImageNet datasets.

The APT attack on the Internet is becoming more serious, and most of intrusion detection systems can only generate alarms to some steps of APT attack and cannot identify the pattern of the APT attack. To detect APT attack, many researchers established attack models and then correlated IDS logs with the attack models. However, the accuracy of detection deeply relied on the integrity of models. In this paper, we propose a new method to construct APT attack scenarios by mining IDS security logs. These APT attack scenarios can be further used for the APT detection. First, we classify all the attack events by purpose of phase of the intrusion kill chain. Then we add the attack event dimension to fuzzy clustering, correlate IDS alarm logs with fuzzy clustering, and generate the attack sequence set. Next, we delete the bug attack sequences to clean the set. Finally, we use the nonaftereffect property of probability transfer matrix to construct attack scenarios by mining the attack sequence set. Experiments show that the proposed method can construct the APT attack scenarios by mining IDS alarm logs, and the constructed scenarios match the actual situation so that they can be used for APT attack detection.

With the improvement of steganography, the difference of statistical distribution caused by information hiding is getting smaller and smaller, increasing the difficulty of steganalysis. The existing steganalysis models value different features equally, while the differences in the importance of high-dimensional features are ignored. That is the influences of feature quality on model performance are not considered. To fill the gap, a novel linguistic steganalysis by enhancing and integrating local and global features is proposed in this letter. It extracts and integrates the features of two dimensions, namely local semantic features and global long-term dependencies, to construct a joint feature map. Then, to improve the quality of features, a group-wise enhancement mechanism is employed, which divides features into multiple groups, enhancing important features in each group while weakening the less important ones by generating an important coefficient for each sub-feature in each semantic group. Finally, the enhanced features are used to further extract high-quality text representation to help the classification module distinguish cover and stego texts more accurately. The experimental results show that the proposed model has better detection performance in multiple hidden scenarios. The ablation experiment manifests that using integrated and enhanced features to extract high-quality text representations can effectively improve the discrimination ability of the model.

Recent relation extraction models’ architecture are evolved from the shallow neural networks to natural language model, such as convolutional neural networks or recurrent neural networks to Bert. However, these methods did not consider the semantic information in the sequence or the distance dependence problem, the internal semantic information may contain the useful knowledge which can help relation classification. Focus on these problems, this paper proposed a BERT-based relation classification method. Compare with the existing Bert-based architecture, the proposed model can obtain the internal semantic information between entity pair and solve the distance semantic dependence better. The pre-trained BERT model after fine tuning is used in this paper to abstract the semantic representation of sequence, then adopt the piecewise convolution to obtain semantic information which influence the extraction results. Compare with the existing methods, the proposed method can achieve a better accuracy on relational extraction task because of the internal semantic information extracted in the sequence. While, the generalization ability is still a problem that cannot be ignored, and the numbers of the relationships are difference between different categories. In this paper, the focal loss function is adopted to solve this problem by assigning a heavy weight to less number or hard classify categories. Finally, comparing with the existing methods, the F1 metric of the proposed method can reach a superior result 89.95% on the SemEval-2010 Task 8 dataset.

When the data undergo a distribution change, existing linguistic steganalysis often struggles to effectively capture the statistical characteristics of the transformed cover or stego, resulting in a drop in performances. To address this issue and fully use the information from the original data before the change, this letter proposes a reinforcement learning-based method for linguistic steganalysis. This method employs an agent (steganalyzer) to interact within an observation space, enabling adaptation to the characteristics of the transformed data and capturing steganalysis features. Specifically, we map the texts to the GloVe observation space and construct an agent comprising Actor module and Critic module to provide action, state, and other information. In the pre-training phase, agent trains and reinforces the Actor and Critic modules using the original data before the change. In the fine-tuning phase, agent optimizes these two modules to extract steganalysis feature through reinforcement training with instant reward in the transformed data. Experiments show that the proposed method exhibits better performances than the baseline in the transformed scenarios. Furthermore, this method offers a more autonomous training solution for linguistic steganalysis.