An Evolutionary Computing Enriched RS Attack Resilient Medical Image Steganography Model for Telemedicine Applications

The recent advancement in computing technologies and resulting vision based applications have gives rise to a novel practice called telemedicine that requires patient diagnosis images or allied information to recommend or even perform diagnosis practices being located remotely. However, to ensure accurate and optimal telemedicine there is the requirement of seamless or flawless biomedical information about patient. On the contrary, medical data transmitted over insecure channel often remains prone to get manipulated or corrupted by attackers. The existing cryptosystems alone are not sufficient to deal with these issues and hence in this paper a highly robust reversible image steganography model has been developed for secret information hiding. Unlike traditional wavelet transform techniques, we incorporated Discrete Ripplet Transformation (DRT) technique for message embedding in the medical cover images. In addition, to assure seamless communication over insecure channel, a dual cryptosystem model containing proposed steganography scheme and RSA cryptosystem has been developed. One of the key novelties of the proposed research work is the use of adaptive genetic algorithm (AGA) for optimal pixel adjustment process (OPAP) that enriches data hiding capacity as well as imperceptibility features. The performance assessment reveals that the proposed steganography model outperforms other wavelet transformation based approaches in terms of high PSNR, embedding capacity, imperceptibility etc.Comment: 14 page / 3 figures / 6 tables, Multidimensional Systems and Signal Processing 201

Arabic Text Watermarking: A Review

The using of the internet with its technologies and applications have been increased rapidly. So, protecting the text from illegal use is too needed . Text watermarking is used for this purpose. Arabic text has many characteristics such existing of diacritics , kashida (extension character) and points above or under its letters .Each of Arabic letters can take different shapes with different Unicode. These characteristics are utilized in the watermarking process. In this paper, several methods are discussed in the area of Arabic text watermarking with its advantages and disadvantages .Comparison of these methods is done in term of capacity, robustness and Imperceptibility.Comment: 16 pages, 4 tables and 19 figure

Trends toward real-time network data steganography

Network steganography has been a well-known covert data channeling method for over three decades. The basic set of techniques and implementation tools have not changed significantly since their introduction in the early 1980's. In this paper, we review the predominant methods of classical network steganography, describing the detailed operations and resultant challenges involved in embedding data in the network transport domain. We also consider the various cyber threat vectors of network steganography and point out the major differences between classical network steganography and the widely known end-point multimedia embedding techniques, which focus exclusively on static data modification for data hiding. We then challenge the security community by introducing an entirely new network dat hiding methodology, which we refer to as real-time network data steganography. Finally we provide the groundwork for this fundamental change of covert network data embedding by forming a basic framework for real-time network data operations that will open the path for even further advances in computer network security.Comment: 20 pages introducing the concept of real-time network steganograph

Combined Image Encryption and Steganography Algorithm in the Spatial Domain

In recent years, steganography has emerged as one of the main research areas in information security. Least significant bit (LSB) steganography is one of the fundamental and conventional spatial domain methods, which is capable of hiding larger secret information in a cover image without noticeable visual distortions. In this paper, a combined algorithm based on LSB steganography and chaotic encryption is proposed. Experimental results show the feasibility of the proposed method. In comparison with existing steganographic spatial domain based algorithms, the suggested algorithm is shown to have some advantages over existing ones, namely, larger key space and a higher level of security against some existing attacks.Comment: 6 page

Low Bit-Rate and High Fidelity Reversible Data Hiding

An accurate predictor is crucial for histogram-shifting (HS) based reversible data hiding methods. The embedding capacity is increased and the embedding distortion is decreased simultaneously if the predictor can generate accurate predictions. In this paper, we propose an accurate linear predictor based on weighted least squares (WLS) estimation. The robustness of WLS helps the proposed predictor generate accurate predictions, especially in complex texture areas of an image, where other predictors usually fail. To further reduce the embedding distortion, we propose a new embedding method called dynamic histogram shifting with pixel selection (DHS-PS) that selects not only the proper histogram bins but also the proper pixel locations to embed the given data. As a result, the proposed method can obtain very high fidelity marked images with low bit-rate data embedded. The experimental results show that the proposed method outperforms the state-of-the-art low bit-rate reversible data hiding method

Adversarial Audio: A New Information Hiding Method and Backdoor for DNN-based Speech Recognition Models

Audio is an important medium in people's daily life, hidden information can be embedded into audio for covert communication. Current audio information hiding techniques can be roughly classed into time domain-based and transform domain-based techniques. Time domain-based techniques have large hiding capacity but low imperceptibility. Transform domain-based techniques have better imperceptibility, but the hiding capacity is poor. This paper proposes a new audio information hiding technique which shows high hiding capacity and good imperceptibility. The proposed audio information hiding method takes the original audio signal as input and obtains the audio signal embedded with hidden information (called stego audio) through the training of our private automatic speech recognition (ASR) model. Without knowing the internal parameters and structure of the private model, the hidden information can be extracted by the private model but cannot be extracted by public models. We use four other ASR models to extract the hidden information on the stego audios to evaluate the security of the private model. The experimental results show that the proposed audio information hiding technique has a high hiding capacity of 48 cps with good imperceptibility and high security. In addition, our proposed adversarial audio can be used to activate an intrinsic backdoor of DNN-based ASR models, which brings a serious threat to intelligent speakers.Comment: Submitted to RAID201

Hiding Information in Noise: Fundamental Limits of Covert Wireless Communication

Widely-deployed encryption-based security prevents unauthorized decoding, but does not ensure undetectability of communication. However, covert, or low probability of detection/intercept (LPD/LPI) communication is crucial in many scenarios ranging from covert military operations and the organization of social unrest, to privacy protection for users of wireless networks. In addition, encrypted data or even just the transmission of a signal can arouse suspicion, and even the most theoretically robust encryption can often be defeated by a determined adversary using non-computational methods such as side-channel analysis. Various covert communication techniques were developed to address these concerns, including steganography for finite-alphabet noiseless applications and spread-spectrum systems for wireless communications. After reviewing these covert communication systems, this article discusses new results on the fundamental limits of their capabilities, as well as provides a vision for the future of such systems.Comment: 6 pages, 4 figure

Information Hiding as a Challenge for Malware Detection

Information hiding techniques are increasingly utilized by the current malware to hide its existence and communication attempts. In this paper we highlight this new trend by reviewing the most notable examples of malicious software that shows this capability.Comment: 9 pages, 1 tabl

Hiding Data in Plain Sight: Undetectable Wireless Communications Through Pseudo-Noise Asymmetric Shift Keying

Undetectable wireless transmissions are fundamental to avoid eavesdroppers. To address this issue, wireless steganography hides covert information inside primary information by slightly modifying the transmitted waveform such that primary information will still be decodable, while covert information will be seen as noise by agnostic receivers. Since the addition of covert information inevitably decreases the SNR of the primary transmission, key challenges in wireless steganography are: i) to assess the impact of the covert channel on the primary channel as a function of different channel conditions; and ii) to make sure that the covert channel is undetectable. Existing approaches are protocol-specific, also we notice that existing wireless technologies rely on phase-keying modulations that in most cases do not use the channel up to its Shannon capacity. Therefore, the residual capacity can be leveraged to implement a wireless system based on a pseudo-noise asymmetric shift keying (PN-ASK) modulation, where covert symbols are mapped by shifting the amplitude of primary symbols. This way, covert information will be undetectable, since a receiver expecting phase-modulated symbols will see their shift in amplitude as an effect of channel/path loss degradation. We first investigate the SER of PN-ASK as a function of the channel; then, we find the optimal PN-ASK parameters that optimize primary and covert throughput under different channel condition. We evaluate the throughput performance and undetectability of PN-ASK through extensive simulations and on an experimental testbed based on USRP N210 software-defined radios. We show that PN-ASK improves the throughput by more than 8x with respect to prior art. Finally, we demonstrate through experiments that PN-ASK is able to transmit covert data on top of IEEE 802.11g frames, which are correctly decoded by an off-the-shelf laptop WiFi

On the Unicity Distance of Stego Key

Steganography is about how to send secret message covertly. And the purpose of steganalysis is to not only detect the existence of the hidden message but also extract it. So far there have been many reliable detecting methods on various steganographic algorithms, while there are few approaches that can extract the hidden information. In this paper, the difficulty of extracting hidden information, which is essentially a kind of privacy, is analyzed with information-theoretic method in the terms of unicity distance of steganographic key (abbreviated stego key). A lower bound for the unicity distance is obtained, which shows the relations between key rate, message rate, hiding capacity and difficulty of extraction. Furthermore the extracting attack to steganography is viewed as a special kind of cryptanalysis, and an effective method on recovering the stego key of popular LSB replacing steganography in spatial images is presented by combining the detecting technique of steganalysis and correlation attack of cryptanalysis together. The analysis for this method and experimental results on steganographic software ``Hide and Seek 4.1" are both accordant with the information-theoretic conclusion.Comment: 8 pages, 3 figure