Biblio

Over the years, operating systems (OSs) have grown significantly in complexity and size providing attackers with more avenues to compromise their security. By eliminating the OS, it becomes possible to develop general-purpose non-embedded applications that are free of typical OS-related vulnerabilities. Such applications are simpler and smaller in size, making it easier secure the application code. Bare machine computing (BMC) applications run on ordinary desktops and laptops without the support of any operating system or centralized kernel. Many BMC applications have been developed previously for single-core systems. We show how to build BMC applications for multicore systems by presenting the design and implementation of a novel UDP-based bare machine prototype Web server for a multicore architecture. We also include preliminary experimental results from running the server on the Internet. This work provides a foundation for building secure computer applications that run on multicore systems without the need for intermediary software.

Due to the computing capability limitation of the Internet of things devices in the perception layer, the traditional security solutions are difficult to be used directly. How to design a new lightweight, secure and reliable protocol suitable for the Internet of Things application environment, and realize the secure transmission of information among many sensing checkpoints is an urgent problem to be solved. In this paper, we propose a decentralized lightweight authentication key protocol based on the combination of public key and trusted computing technology, which is used to establish secure communication between nodes in the perception layer. The various attacks that the protocol may suffer are analyzed, and the formal analysis method is used to verify the security of the protocol. To verify the validity of the protocol, the computation and communication cost of the protocol are compared with the existing key protocols. And the results show that the protocol achieved the promised performance.

We present a novel approach for the collaborative training of neural network models in decentralized federated environments. In the iterative process a group of autonomous peers run multiple training rounds to train a common model. Thereby, participants perform all model training steps locally, such as stochastic gradient descent optimization, using their private, e.g. mission-critical, training datasets. Based on locally updated models, participants can jointly determine a common model by averaging all associated model weights without sharing the actual weight values. For this purpose we introduce a simple n-out-of-n secret sharing schema and an algorithm to calculate average values in a peer-to-peer manner. Our experimental results with deep neural networks on well-known sample datasets prove the generic applicability of the approach, with regard to model quality parameters. Since there is no need to involve a central service provider in model training, the approach can help establish trustworthy collaboration platforms for businesses with high security and data protection requirements.

With the increasing popularity of geo-positioning technologies and mobile Internet, spatial keyword data services have attracted growing interest from both the industrial and academic communities in recent years. Meanwhile, a massive amount of data is increasingly being outsourced to cloud in the encrypted form for enjoying the advantages of cloud computing while without compromising data privacy. Most existing works primarily focus on the privacy-preserving schemes for either spatial or keyword queries, and they cannot be directly applied to solve the spatial keyword query problem over encrypted data. In this paper, we study the challenging problem of Privacy-preserving Boolean Range Query (PBRQ) over encrypted spatial databases. In particular, we propose two novel PBRQ schemes. Firstly, we present a scheme with linear search complexity based on the space-filling curve code and Symmetric-key Hidden Vector Encryption (SHVE). Then, we use tree structures to achieve faster-than-linear search complexity. Thorough security analysis shows that data security and query privacy can be guaranteed during the query process. Experimental results using real-world datasets show that the proposed schemes are efficient and feasible for practical applications, which is at least ×70 faster than existing techniques in the literature.

In this work, the efficient evaluation of Sommerfeld integrals (SIs) above an impedance plane is addressed. Started from Weyl's expression of SIs, using the coordinate transformation and steepest descent path approach, an exact single image representation to SIs is derived. This single image representation image eliminates oscillating and slow-decay integrand in traditional SIs, and efficient to calculate. Moreover, the far-field asymptotic behavior of SIs in this case is considered and is represented by the Fresnel-integral related function. A high-order approximation based on series expansion of Fresnel integral is provided for fast evaluation. Finally, the validity of the proposed expressions is verified by numerical examples.

We propose thrombolysis using a magnetic nanoparticle microswarm with tissue plasminogen activator (tPA) under ultrasound imaging. The microswarm is generated in blood using an oscillating magnetic field and can be navigated with locomotion along both the long and short axis. By modulating the input field, the aspect ratio of the microswarm can be reversibly tuned, showing the ability to adapt to different confined environments. Simulation results indicate that both in-plane and out-of-plane fluid convection are induced around the microswarm, which can be further enhanced by tuning the aspect ratio of the microswarm. Under ultrasound imaging, the microswarm is navigated in a microchannel towards a blood clot and deformed to obtain optimal lysis. Experimental results show that the lysis rate reaches -0.1725 ± 0.0612 mm3/min in the 37°C blood environment under the influence of the microswarm-induced fluid convection and tPA. The lysis rate is enhanced 2.5-fold compared to that without the microswarm (-0.0681 ± 0.0263 mm3/min). Our method provides a new strategy to increase the efficiency of thrombolysis by applying microswarm-induced fluid convection, indicating that swarming micro/nanorobots have the potential to act as effective tools towards targeted therapy.

The collection of digital information by governments, companies and individuals creates tremendous opportunities for knowledge and information-based decision-making. Driven by mutual benefit and laws and regulations, there is a need for data exchange and publication between all parties. However, data in its original form usually contains sensitive information about individuals and publishing such data would violate personal privacy. Privacy Protection Data Distribution (PPDP) provides methods and tools to release useful information while protecting data privacy. In recent years, PPDP has received extensive attention from the research community, and many solutions have been proposed for different data release scenarios. How to ensure the availability of data under the premise of protecting user privacy is the core problem to be solved in this field. This paper studies the existing achievements of privacy protection data release anonymity technology, focusing on the existing anonymity technology in three aspects of high-dimensional, high-deficiency, and complex relational data, and analyzes and summarizes them.

Speaker verification has been widely and successfully adopted in many mission-critical areas for user identification. The training of speaker verification requires a large amount of data, therefore users usually need to adopt third-party data (e.g., data from the Internet or third-party data company). This raises the question of whether adopting untrusted third-party data can pose a security threat. In this paper, we demonstrate that it is possible to inject the hidden backdoor for infecting speaker verification models by poisoning the training data. Specifically, we design a clustering-based attack scheme where poisoned samples from different clusters will contain different triggers (i.e., pre-defined utterances), based on our understanding of verification tasks. The infected models behave normally on benign samples, while attacker-specified unenrolled triggers will successfully pass the verification even if the attacker has no information about the enrolled speaker. We also demonstrate that existing back-door attacks cannot be directly adopted in attacking speaker verification. Our approach not only provides a new perspective for designing novel attacks, but also serves as a strong baseline for improving the robustness of verification methods. The code for reproducing main results is available at https://github.com/zhaitongqing233/Backdoor-attack-against-speaker-verification.

As an innovative type of decentralized model, blockchain is a growing list of blocks linked by cryptography. Blockchain incorporates anonymity protocol, distributed data storage, consensus algorithm, and smart contract. The anonymity protocols in blockchain are significant in that they could protect users from leaking their personal information. In this paper, we will conduct a detailed review and comparison of anonymity protocols used in three famous cryptocurrencies, namely Bitcoin, Zcash, and Ethereum.

k-anonymity is a well-known definition of privacy, which guarantees that any person in the released dataset cannot be distinguished from at least k-1 other individuals. In the protection model, the records are anonymized through generalization or suppression with a fixed value of k. Accordingly, each record has the same level of anonymity in the published dataset. However, different people or items usually have inconsistent privacy requirements. Some records need extra protection while others require a relatively low level of privacy constraint. In this paper, we propose Multi-Level Privacy Preserving K-Anonymity, an advanced protection model based on k-anonymity, which divides records into different groups and requires each group to satisfy its respective privacy requirement. Moreover, we present a practical algorithm using clustering techniques to ensure the property. The evaluation on a real-world dataset confirms that the proposed method has the advantages of offering more flexibility in setting privacy parameters and providing higher data utility than traditional k-anonymity.

In machine learning Trojan attacks, an adversary trains a corrupted model that obtains good performance on normal data but behaves maliciously on data samples with certain trigger patterns. Several approaches have been proposed to detect such attacks, but they make undesirable assumptions about the attack strategies or require direct access to the trained models, which restricts their utility in practice.This paper addresses these challenges by introducing a Meta Neural Trojan Detection (MNTD) pipeline that does not make assumptions on the attack strategies and only needs black-box access to models. The strategy is to train a meta-classifier that predicts whether a given target model is Trojaned. To train the meta-model without knowledge of the attack strategy, we introduce a technique called jumbo learning that samples a set of Trojaned models following a general distribution. We then dynamically optimize a query set together with the meta-classifier to distinguish between Trojaned and benign models.We evaluate MNTD with experiments on vision, speech, tabular data and natural language text datasets, and against different Trojan attacks such as data poisoning attack, model manipulation attack, and latent attack. We show that MNTD achieves 97% detection AUC score and significantly outperforms existing detection approaches. In addition, MNTD generalizes well and achieves high detection performance against unforeseen attacks. We also propose a robust MNTD pipeline which achieves around 90% detection AUC even when the attacker aims to evade the detection with full knowledge of the system.

Due to respectively limited training data, different entities addressing the same vision task based on certain sensitive images may not train a robust deep network. This paper introduces a new vision task where various entities share task-specific image data to enlarge each other's training data volume without visually disclosing sensitive contents (e.g. illegal images). Then, we present a new structure-based training regime to enable different entities learn task-specific and reconstruction-proof image representations for image data sharing. Specifically, each entity learns a private Deep Poisoning Module (DPM) and insert it to a pre-trained deep network, which is designed to perform the specific vision task. The DPM deliberately poisons convolutional image features to prevent image reconstructions, while ensuring that the altered image data is functionally equivalent to the non-poisoned data for the specific vision task. Given this equivalence, the poisoned features shared from one entity could be used by another entity for further model refinement. Experimental results on image classification prove the efficacy of the proposed method.

Malware classification helps to understand its purpose and is also an important part of attack detection. And it is also an important part of discovering attacks. Due to continuous innovation and development of artificial intelligence, it is a trend to combine deep learning with malware classification. In this paper, we propose an improved malware image rescaling algorithm (IMIR) based on local mean algorithm. Its main goal of IMIR is to reduce the loss of information from samples during the process of converting binary files to image files. Therefore, we construct a neural network structure based on VGG model, which is suitable for image classification. In the real world, a mass of malware family labels are inaccurate or lacking. To deal with this situation, we propose a novel method to train the deep neural network by Semi-supervised Generative Adversarial Network (SGAN), which only needs a small amount of malware that have accurate labels about families. By integrating SGAN with weak coupling, we can retain the weak links of supervised part and unsupervised part of SGAN. It improves the accuracy of malware classification by making classifiers more independent of discriminators. The results of experimental demonstrate that our model achieves exhibiting favorable performance. The recalls of each family in our data set are all higher than 93.75%.

Device-to-Device (D2D) communications play a key role in the mobile communication networks. In spite of its benefits, new system architecture expose the D2D communications to unique security threats. Due to D2D users share the same licensed spectrum resources with the cellular users, both the cellular user and D2D receiver can eavesdrop each other's critical information. Thus, to maximize the secrecy rate from the perspective of physical layer security, the letter proposed a optimal power allocation scheme and subsequently to optimization problem of resource allocation is systematically investigated. The efficacy of the proposed scheme is assessed numerically.

With the emergence and development of quantum computers, the traditional public-key cryptography (PKC) is facing the risk of being cracked. In order to resist quantum attacks and ensure long-term communication security, NIST launched a global collection of Post Quantum Cryptography (PQC) standards in 2016, and it is currently in the third round of selection. There are three Lattice-based PKC algorithms that stand out, and NTRU is one of them. In this article, we proposed the first complete and compact full hardware implementation of NTRU algorithm submitted in the third round. By using one structure to complete the design of the three types of complex polynomial multiplications in the algorithm, we achieved better performance while reducing area costs.

Usually on the top of Smart Chip covered with active shielding layer to prevent invasive physical exploration tampering attacks on part of the chip's function modules, to obtain the chip's critical storage data and sensitive information. This paper introduces a design based on UMC55 technology, and applied to the safety chip active shielding layer method for layout design, the layout design from the two aspects of the metal shielding line and shielding layer detecting circuit, using the minimum size advantage and layout design process when the depth of hidden shielding line interface and port order connection method and greatly increased the difficulty of physical attack. The layout design can withstand most of the current FIB physical attack technology, and has been applied to the actual smart card design, and it has important practical significance for the security design and attack of the chip.

The task of malware labeling on real datasets faces huge challenges—ever-changing datasets and lack of ground-truth labels—owing to the rapid growth of malware. Clustering malware on their respective families is a well known tool used for improving the efficiency of the malware labeling process. In this paper, we addressed the challenge of clustering email malware, and carried out a cluster analysis on a real dataset collected from email campaigns over a 13-month period. Our main original contribution is to analyze the usefulness of email’s header information for malware clustering (a novel approach proposed by Burton [1]), and compare it with features collected from the malware directly. We compare clustering based on email header’s information with traditional features extracted from varied resources provided by VirusTotal [2], including static and dynamic analysis. We show that email header information has an excellent performance.

The power terminal network has the characteristics of a large number of nodes, various types, and complex network topology. After the power terminal network is attacked, the impact of power terminals in different business scenarios is also different. Traditional impact assessment methods based on network traffic or power system operation rules are difficult to achieve comprehensive attack impact analysis. In this paper, from the three levels of terminal security itself, terminal network security and terminal business application security, it constructs quantitative indicators for analyzing the impact of power terminals after being attacked, so as to determine the depth and breadth of the impact of the attack on the power terminal network, and provide the next defense measures with realistic basis.

This paper analyzes the current situation and shortcomings of traditional security chip production program management, then proposes a management approach of a chip issue program management method and develope a management system based on Webservice technology. The program management method and system of chip production proposed in this paper simplifies the program management process of chip production and improves the working efficiency of chip production management.

The power communication network generates a large amount of data. The existing security monitoring method needs to use a large transmission bandwidth in the process of data processing, which leads to the decrease of real-time response. Therefore, an automatic monitoring method of power communication network security based on edge computing is proposed. The paper establishes the power communication monitoring network architecture by combining RFID identification sensor network and wireless communication network. The edge calculation is embedded to the edge side of the power communication network, and the data processing model of power communication is established. Based on linear discriminant analysis, the paper designs a network security situation awareness assessment model, and uses this model to evaluate the real-time data collected by the power communication network. According to the evaluation results, the probability of success of intrusion attack is calculated and the security risk monitoring is carried out for the intrusion attack. The experimental results show that compared with the existing monitoring methods, the edge based security monitoring method can effectively reduce communication delay, improve the real-time response, and then improve the intelligent level of power communication network.

Resilience has been defined as a priority for the US critical infrastructure. This paper presents a process for incorporating resiliency-derived metrics into security system evaluations. To support this analysis, we used a multi-layer network model (MLN) reflecting the defined security system of a hypothetical nuclear power plant to define what metrics would be useful in understanding a system’s ability to absorb perturbation (i.e., system resilience). We defined measures focusing on the system’s criticality, rapidity, diversity, and confidence at each network layer, simulated adversary path, and the system as a basis for understanding the system’s resilience. For this hypothetical system, our metrics indicated the importance of physical infrastructure to overall system criticality, the relative confidence of physical sensors, and the lack of diversity in assessment activities (i.e., dependence on human evaluations). Refined model design and data outputs will enable more nuanced evaluations into temporal, geospatial, and human behavior considerations. Future studies can also extend these methodologies to capture respond and recover aspects of resilience, further supporting the protection of critical infrastructure.

Many industrial control systems (ICS) are reliant upon programmable logic controllers (PLCs) for their operations. As ICS and PLCs are increasingly targeted by cyber-attacks, research facilitating the resiliency of their physical processes is imperative. This paper proposes an approach which leverages PLC containerization, input/output (I/O) multiplexing, and orchestration to respond to cyber incidents and ensure continuity of critical processes. A proofof-concept capability was developed and evaluated on live ICS testbed environments. The experimental results indicate the approach is viable for control applications with soft real-time requirements.

Signcryption is a sophisticated cryptographic tool that combines the benefits of digital signature and data encryption in a single step, resulting in reduced computation and storage cost. However, the existing signcryption techniques do not account for a scenario in which a company must escrow an employee's private encryption key so that the corporation does not lose the capacity to decrypt a ciphertext when the employee or user is no longer available. To circumvent the issue of non-repudiation, the private signing key does not need to be escrowed. As a result, this paper presents an implicit certificate-based signcryption technique with private encryption key escrow, which can assist an organization in preventing the loss of private encryption. A certificate, or more broadly, a digital signature, protects users' public encryption and signature keys from man-in-the-middle attacks under our proposed approach.

The circulating current in the D-winding may cause primary current waveform distortion, and the reliability of the restraint criterion based on the typical magnetizing inrush current characteristics will be affected. The magnetizing inrush current with typical characteristics is the sum of primary current and circulating current. Using the circulating current to compensate the primary current can improve the reliability of the differential protection. When the phase is not saturated, the magnetizing inrush current is about zero. Therefore, the primary current of unsaturated phase can be replaced by the opposite of the circulating current. Based on this, an engineering practical calculation method for circulating current is proposed. In the method, the segmented primary currents are used to replace the circulating current. Phasor analysis is used to demonstrate the application effect of this method when remanence coefficients are different. The method is simple and practical, and has strong applicability and high reliability. Simulation and recorded waveforms have verified the effectiveness of the method.

Magnetic shielding is an important part in atomic clock’s physical system. The demagnetization of the assembled magnetic shielding system plays an important role in improving atomic clock’s performance. In terms of the drawbacks in traditional attenuated alternating-current demagnetizing method, this paper proposes a novel method — automatically attenuated alternating-current demagnetizing method. Which is implemented by controlling the demagnetization current waveform thorough the signal source’s modulation, so that these parameters such as demagnetizing current frequency, amplitude, transformation mode and demagnetizing period are precisely adjustable. At the same time, this demagnetization proceeds automatically, operates easily, and works steadily. We have the pulsed optically pumped (POP) rubidium atomic clock’s magnetic shielding system for the demagnetization experiment, the magnetic field value reached 1nT/7cm. Experiments show that novel method can effectively realize the demagnetization of the magnetic shielding system, and well meets the atomic clock’s working requirements.