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2018-02-14
Liu, Z., Liao, Y., Yang, X., He, Y., Zhao, K..  2017.  Identity-Based Remote Data Integrity Checking of Cloud Storage From Lattices. 2017 3rd International Conference on Big Data Computing and Communications (BIGCOM). :128–135.
In cloud storage, remote data integrity checking is considered as a crucial technique about data owners who upload enormous data to cloud server provider. A majority of the existing remote data integrity checking protocols rely on the expensive public key infrastructure. In addition, the verification of certificates needs heavy computation and communication cost. Meanwhile, the existing some protocols are not secure under the quantum computer attacks. However, lattice-based constructed cryptography can resist quantum computer attacks and is fairly effective, involving matrix-matrix or matrix-vector multiplications. So, we propose an identity-based remote data integrity checking protocol from lattices, which can eliminate the certificate management process and resist quantum computer attacks. Our protocol is completeness and provably secure based on the hardness small integer solution assumption. The presented scheme is secure against cloud service provider attacks, and leaks no any blocks of the stored file to the third party auditor during verification stage, namely the data privacy against the curiosity third party auditor attacks. The cloud service provider attack includes lost attack and tamper attack. Furthermore, the performance analysis of some protocols demonstrate that our protocol of remote data integrity checking is useful and efficient.
Naik, N., Jenkins, P..  2017.  Securing digital identities in the cloud by selecting an apposite Federated Identity Management from SAML, OAuth and OpenID Connect. 2017 11th International Conference on Research Challenges in Information Science (RCIS). :163–174.
Access to computer systems and the information held on them, be it commercially or personally sensitive, is naturally, strictly controlled by both legal and technical security measures. One such method is digital identity, which is used to authenticate and authorize users to provide access to IT infrastructure to perform official, financial or sensitive operations within organisations. However, transmitting and sharing this sensitive information with other organisations over insecure channels always poses a significant security and privacy risk. An example of an effective solution to this problem is the Federated Identity Management (FIdM) standard adopted in the cloud environment. The FIdM standard is used to authenticate and authorize users across multiple organisations to obtain access to their networks and resources without transmitting sensitive information to other organisations. Using the same authentication and authorization details among multiple organisations in one federated group, it protects the identities and credentials of users in the group. This protection is a balance, mitigating security risk whilst maintaining a positive experience for users. Three of the most popular FIdM standards are Security Assertion Markup Language (SAML), Open Authentication (OAuth), and OpenID Connect (OIDC). This paper presents an assessment of these standards considering their architectural design, working, security strength and security vulnerability, to cognise and ascertain effective usages to protect digital identities and credentials. Firstly, it explains the architectural design and working of these standards. Secondly, it proposes several assessment criteria and compares functionalities of these standards based on the proposed criteria. Finally, it presents a comprehensive analysis of their security vulnerabilities to aid in selecting an apposite FIdM. This analysis of security vulnerabilities is of great significance because their improper or erroneous deployme- t may be exploited for attacks.
Kimiyama, H., Yonezaki, N., Tsutsumi, T., Sano, K., Yamaki, H., Ueno, Y., Sasaki, R., Kobayashi, H..  2017.  Autonomous and distributed internet security (AIS) infrastructure for safe internet. 2017 8th International Conference on the Network of the Future (NOF). :106–113.

Cyber attacks, (e.g., DDoS), on computers connected to the Internet occur everyday. A DDoS attack in 2016 that used “Mirai botnet” generated over 600 Gbit/s traffic, which was twice as that of last year. In view of this situation, we can no longer adequately protect our computers using current end-point security solutions and must therefore introduce a new method of protection that uses distributed nodes, e.g., routers. We propose an Autonomous and Distributed Internet Security (AIS) infrastructure that provides two key functions: first, filtering source address spoofing packets (proactive filter), and second, filtering malicious packets that are observed at the end point (reactive filter) at the closest malicious packets origins. We also propose three types of Multi-Layer Binding Routers (MLBRs) to realize these functions. We implemented the MLBRs and constructed experimental systems to simulate DDoS attacks. Results showed that all malicious packets could be filtered by using the AIS infrastructure.

2018-02-06
Brannsten, M. R., Bloebaum, T. H., Johnsen, F. T., Reitan, B. K..  2017.  Kings Eye: Platform Independent Situational Awareness. 2017 International Conference on Military Communications and Information Systems (ICMCIS). :1–5.

Kings Eye is a platform independent situational awareness prototype for smart devices. Platform independence is important as there are more and more soldiers bringing their own devices, with different operating systems, into the field. The concept of Bring Your Own Device (BYOD) is a low-cost approach to equipping soldiers with situational awareness tools and by this it is important to facilitate and evaluate such solutions.

Eslami, M., Zheng, G., Eramian, H., Levchuk, G..  2017.  Anomaly Detection on Bipartite Graphs for Cyber Situational Awareness and Threat Detection. 2017 IEEE International Conference on Big Data (Big Data). :4741–4743.

Data from cyber logs can often be represented as a bipartite graph (e.g. internal IP-external IP, user-application, or client-server). State-of-the-art graph based anomaly detection often generalizes across all types of graphs — namely bipartite and non-bipartite. This confounds the interpretation and use of specific graph features such as degree, page rank, and eigencentrality that can provide a security analyst with rapid situational awareness of their network. Furthermore, graph algorithms applied to data collected from large, distributed enterprise scale networks require accompanying methods that allow them to scale to the data collected. In this paper, we provide a novel, scalable, directional graph projection framework that operates on cyber logs that can be represented as bipartite graphs. This framework computes directional graph projections and identifies a set of interpretable graph features that describe anomalies within each partite.

Scheitle, Q., Gasser, O., Rouhi, M., Carle, G..  2017.  Large-Scale Classification of IPv6-IPv4 Siblings with Variable Clock Skew. 2017 Network Traffic Measurement and Analysis Conference (TMA). :1–9.

Linking the growing IPv6 deployment to existing IPv4 addresses is an interesting field of research, be it for network forensics, structural analysis, or reconnaissance. In this work, we focus on classifying pairs of server IPv6 and IPv4 addresses as siblings, i.e., running on the same machine. Our methodology leverages active measurements of TCP timestamps and other network characteristics, which we measure against a diverse ground truth of 682 hosts. We define and extract a set of features, including estimation of variable (opposed to constant) remote clock skew. On these features, we train a manually crafted algorithm as well as a machine-learned decision tree. By conducting several measurement runs and training in cross-validation rounds, we aim to create models that generalize well and do not overfit our training data. We find both models to exceed 99% precision in train and test performance. We validate scalability by classifying 149k siblings in a large-scale measurement of 371k sibling candidates. We argue that this methodology, thoroughly cross-validated and likely to generalize well, can aid comparative studies of IPv6 and IPv4 behavior in the Internet. Striving for applicability and replicability, we release ready-to-use source code and raw data from our study.

Sun, J., Sun, K., Li, Q..  2017.  CyberMoat: Camouflaging Critical Server Infrastructures with Large Scale Decoy Farms. 2017 IEEE Conference on Communications and Network Security (CNS). :1–9.

Traditional deception-based cyber defenses often undertake reactive strategies that utilize decoy systems or services for attack detection and information gathering. Unfortunately, the effectiveness of these defense mechanisms has been largely constrained by the low decoy fidelity, the poor scalability of decoy platform, and the static decoy configurations, which allow the attackers to identify and bypass the deployed decoys. In this paper, we develop a decoy-enhanced defense framework that can proactively protect critical servers against targeted remote attacks through deception. To achieve both high fidelity and good scalability, our system follows a hybrid architecture that separates lightweight yet versatile front-end proxies from back-end high-fidelity decoy servers. Moreover, our system can further invalidate the attackers' reconnaissance through dynamic proxy address shuffling. To guarantee service availability, we develop a transparent connection translation strategy to maintain existing connections during shuffling. Our evaluation on a prototype implementation demonstrates the effectiveness of our approach in defeating attacker reconnaissance and shows that it only introduces small performance overhead.

Birnstill, P., Haas, C., Hassler, D., Beyerer, J..  2017.  Introducing Remote Attestation and Hardware-Based Cryptography to OPC UA. 2017 22nd IEEE International Conference on Emerging Technologies and Factory Automation (ETFA). :1–8.

In this paper we investigate whether and how hardware-based roots of trust, namely Trusted Platform Modules (TPMs) can improve the security of the communication protocol OPC UA (Open Platform Communications Unified Architecture) under reasonable assumptions, i.e. the Dolev-Yao attacker model. Our analysis shows that TPMs may serve for generating (RNG) and securely storing cryptographic keys, as cryptocoprocessors for weak systems, as well as for remote attestation. We propose to include these TPM functions into OPC UA via so-called ConformanceUnits, which can serve as building blocks of profiles that are used by clients and servers for negotiating the parameters of a session. Eventually, we present first results regarding the performance of a client-server communication including an additional OPC UA server providing remote attestation of other OPC UA servers.

Berkowsky, J. A., Hayajneh, T..  2017.  Security Issues with Certificate Authorities. 2017 IEEE 8th Annual Ubiquitous Computing, Electronics and Mobile Communication Conference (UEMCON). :449–455.

The current state of the internet relies heavily on SSL/TLS and the certificate authority model. This model has systematic problems, both in its design as well as its implementation. There are problems with certificate revocation, certificate authority governance, breaches, poor security practices, single points of failure and with root stores. This paper begins with a general introduction to SSL/TLS and a description of the role of certificates, certificate authorities and root stores in the current model. This paper will then explore problems with the current model and describe work being done to help mitigate these problems.

Bhattacharya, S., Kumar, C. R. S..  2017.  Ransomware: The CryptoVirus Subverting Cloud Security. 2017 International Conference on Algorithms, Methodology, Models and Applications in Emerging Technologies (ICAMMAET). :1–6.

Cloud computing presents unlimited prospects for Information Technology (IT) industry and business enterprises alike. Rapid advancement brings a dark underbelly of new vulnerabilities and challenges unfolding with alarming regularity. Although cloud technology provides a ubiquitous environment facilitating business enterprises to conduct business across disparate locations, security effectiveness of this platform interspersed with threats which can bring everything that subscribes to the cloud, to a halt raises questions. However advantages of cloud platforms far outweighs drawbacks and study of new challenges helps overcome drawbacks of this technology. One such emerging security threat is of ransomware attack on the cloud which threatens to hold systems and data on cloud network to ransom with widespread damaging implications. This provides huge scope for IT security specialists to sharpen their skillset to overcome this new challenge. This paper covers the broad cloud architecture, current inherent cloud threat mechanisms, ransomware vulnerabilities posed and suggested methods to mitigate it.

Dai, H., Zhu, X., Yang, G., Yi, X..  2017.  A Verifiable Single Keyword Top-k Search Scheme against Insider Attacks over Cloud Data. 2017 3rd International Conference on Big Data Computing and Communications (BIGCOM). :111–116.

With the development of cloud computing and its economic benefit, more and more companies and individuals outsource their data and computation to clouds. Meanwhile, the business way of resource outsourcing makes the data out of control from its owner and results in many security issues. The existing secure keyword search methods assume that cloud servers are curious-but-honest or partial honest, which makes them powerless to deal with the deliberately falsified or fabricated results of insider attacks. In this paper, we propose a verifiable single keyword top-k search scheme against insider attacks which can verify the integrity of search results. Data owners generate verification codes (VCs) for the corresponding files, which embed the ordered sequence information of the relevance scores between files and keywords. Then files and corresponding VCs are outsourced to cloud servers. When a data user performs a keyword search in cloud servers, the qualified result files are determined according to the relevance scores between the files and the interested keyword and then returned to the data user together with a VC. The integrity of the result files is verified by data users through reconstructing a new VC on the received files and comparing it with the received one. Performance evaluation have been conducted to demonstrate the efficiency and result redundancy of the proposed scheme.

Yasumura, Y., Imabayashi, H., Yamana, H..  2017.  Attribute-Based Proxy Re-Encryption Method for Revocation in Cloud Data Storage. 2017 IEEE International Conference on Big Data (Big Data). :4858–4860.

In the big data era, many users upload data to cloud while security concerns are growing. By using attribute-based encryption (ABE), users can securely store data in cloud while exerting access control over it. Revocation is necessary for real-world applications of ABE so that revoked users can no longer decrypt data. In actual implementations, however, revocation requires re-encryption of data in client side through download, decrypt, encrypt, and upload, which results in huge communication cost between the client and the cloud depending on the data size. In this paper, we propose a new method where the data can be re-encrypted in cloud without downloading any data. The experimental result showed that our method reduces the communication cost by one quarter in comparison with the trivial solution where re-encryption is performed in client side.

Verma, D. C., de Mel, G..  2017.  Measures of Network Centricity for Edge Deployment of IoT Applications. 2017 IEEE International Conference on Big Data (Big Data). :4612–4620.

Edge Computing is a scheme to improve the performance, latency and security guidelines for IoT applications. However, edge deployment of an application also comes with additional complexity in management, an increased attack surface for security vulnerability, and could potentially result in a more expensive solution. As a result, the conditions under which an edge deployment of IoT applications delivers a better solution is not always obvious. Metrics which would be able to predict whether or not an IoT application is suitable for edge deployment can provide useful insights to address this question. In this paper, we examine the key performance indicators for IoT applications, namely the responsiveness, scalability and cost models for different types of IoT applications. Our analysis identifies that network centrality of an IoT application is a key characteristic which determines whether or not an IoT application is a good candidate for edge deployment. We discuss the different measures of network centrality that can be used to characterize applications, and the relative performance of edge deployment compared to centralized deployment for various IoT applications.

Zebboudj, S., Brahami, R., Mouzaia, C., Abbas, C., Boussaid, N., Omar, M..  2017.  Big Data Source Location Privacy and Access Control in the Framework of IoT. 2017 5th International Conference on Electrical Engineering - Boumerdes (ICEE-B). :1–5.

In the recent years, we have observed the development of several connected and mobile devices intended for daily use. This development has come with many risks that might not be perceived by the users. These threats are compromising when an unauthorized entity has access to private big data generated through the user objects in the Internet of Things. In the literature, many solutions have been proposed in order to protect the big data, but the security remains a challenging issue. This work is carried out with the aim to provide a solution to the access control to the big data and securing the localization of their generator objects. The proposed models are based on Attribute Based Encryption, CHORD protocol and $μ$TESLA. Through simulations, we compare our solutions to concurrent protocols and we show its efficiency in terms of relevant criteria.

2018-02-02
Pocklassery, G., Kajuruli, V. K., Plusquellic, J., Saqib, F..  2017.  Physical unclonable functions and dynamic partial reconfiguration for security in resource-constrained embedded systems. 2017 IEEE International Symposium on Hardware Oriented Security and Trust (HOST). :116–121.

Authentication and encryption within an embedded system environment using cameras, sensors, thermostats, autonomous vehicles, medical implants, RFID, etc. is becoming increasing important with ubiquitious wireless connectivity. Hardware-based authentication and encryption offer several advantages in these types of resource-constrained applications, including smaller footprints and lower energy consumption. Bitstring and key generation implemented with Physical Unclonable Functions or PUFs can further reduce resource utilization for authentication and encryption operations and reduce overall system cost by eliminating on-chip non-volatile-memory (NVM). In this paper, we propose a dynamic partial reconfiguration (DPR) strategy for implementing both authentication and encryption using a PUF for bitstring and key generation on FPGAs as a means of optimizing the utilization of the limited area resources. We show that the time and energy penalties associated with DPR are small in modern SoC-based architectures, such as the Xilinx Zynq SoC, and therefore, the overall approach is very attractive for emerging resource-constrained IoT applications.

Aslan, M., Matrawy, A..  2016.  Adaptive consistency for distributed SDN controllers. 2016 17th International Telecommunications Network Strategy and Planning Symposium (Networks). :150–157.

In this paper, we introduce the use of adaptive controllers into software-defined networking (SDN) and propose the use of adaptive consistency models in the context of distributed SDN controllers. These adaptive controllers can tune their own configurations in real-time in order to enhance the performance of the applications running on top of them. We expect that the use of such controllers could alleviate some of the emerging challenges in SDN that could have an impact on the performance, security, or scalability of the network. Further, we propose extending the SDN controller architecture to support adaptive consistency based on tunable consistency models. Finally, we compare the performance of a proof-of-concept distributed load-balancing application when it runs on-top of: (1) an adaptive and (2) a non-adaptive controller. Our results indicate that adaptive controllers were more resilient to sudden changes in the network conditions than the non-adaptive ones.

2018-01-23
Moghaddam, F. F., Wieder, P., Yahyapour, R..  2017.  A policy-based identity management schema for managing accesses in clouds. 2017 8th International Conference on the Network of the Future (NOF). :91–98.

Security challenges are the most important obstacles for the advancement of IT-based on-demand services and cloud computing as an emerging technology. Lack of coincidence in identity management models based on defined policies and various security levels in different cloud servers is one of the most challenging issues in clouds. In this paper, a policy- based user authentication model has been presented to provide a reliable and scalable identity management and to map cloud users' access requests with defined polices of cloud servers. In the proposed schema several components are provided to define access policies by cloud servers, to apply policies based on a structural and reliable ontology, to manage user identities and to semantically map access requests by cloud users with defined polices. Finally, the reliability and efficiency of this policy-based authentication schema have been evaluated by scientific performance, security and competitive analysis. Overall, the results show that this model has met defined demands of the research to enhance the reliability and efficiency of identity management in cloud computing environments.

Eslami, M., Zheng, G., Eramian, H., Levchuk, G..  2017.  Deriving cyber use cases from graph projections of cyber data represented as bipartite graphs. 2017 IEEE International Conference on Big Data (Big Data). :4658–4663.

Graph analysis can capture relationships between network entities and can be used to identify and rank anomalous hosts, users, or applications from various types of cyber logs. It is often the case that the data in the logs can be represented as a bipartite graph (e.g. internal IP-external IP, user-application, or client-server). State-of-the-art graph based anomaly detection often generalizes across all types of graphs — namely bipartite and non-bipartite. This confounds the interpretation and use of specific graph features such as degree, page rank, and eigencentrality that can provide a security analyst with situational awareness and even insights to potential attacks on enterprise scale networks. Furthermore, graph algorithms applied to data collected from large, distributed enterprise scale networks require accompanying methods that allow them to scale to the data collected. In this paper, we provide a novel, scalable, directional graph projection framework that operates on cyber logs that can be represented as bipartite graphs. We also present methodologies to further narrow returned results to anomalous/outlier cases that may be indicative of a cyber security event. This framework computes directional graph projections and identifies a set of interpretable graph features that describe anomalies within each partite.

Ethelbert, O., Moghaddam, F. F., Wieder, P., Yahyapour, R..  2017.  A JSON Token-Based Authentication and Access Management Schema for Cloud SaaS Applications. 2017 IEEE 5th International Conference on Future Internet of Things and Cloud (FiCloud). :47–53.

Cloud computing is significantly reshaping the computing industry built around core concepts such as virtualization, processing power, connectivity and elasticity to store and share IT resources via a broad network. It has emerged as the key technology that unleashes the potency of Big Data, Internet of Things, Mobile and Web Applications, and other related technologies; but it also comes with its challenges - such as governance, security, and privacy. This paper is focused on the security and privacy challenges of cloud computing with specific reference to user authentication and access management for cloud SaaS applications. The suggested model uses a framework that harnesses the stateless and secure nature of JWT for client authentication and session management. Furthermore, authorized access to protected cloud SaaS resources have been efficiently managed. Accordingly, a Policy Match Gate (PMG) component and a Policy Activity Monitor (PAM) component have been introduced. In addition, other subcomponents such as a Policy Validation Unit (PVU) and a Policy Proxy DB (PPDB) have also been established for optimized service delivery. A theoretical analysis of the proposed model portrays a system that is secure, lightweight and highly scalable for improved cloud resource security and management.

Keni, H., Earle, M., Min, M..  2017.  Product authentication using hash chains and printed QR codes. 2017 14th IEEE Annual Consumer Communications Networking Conference (CCNC). :319–324.

In this paper, we explore the usage of printed tags to authenticate products. Printed tags are a cheap alternative to RFID and other tag based systems and do not require specialized equipment. Due to the simplistic nature of such printed codes, many security issues like tag impersonation, server impersonation, reader impersonation, replay attacks and denial of service present in RFID based solutions need to be handled differently. We propose a cost-efficient scheme based on static tag based hash chains to address these security threats. We analyze the security characteristics of this scheme and compare it to other product authentication schemes that use RFID tags. Finally, we show that our proposed statically printed QR codes can be at least as secure as RFID tags.

Malathi, V., Balamurugan, B., Eshwar, S..  2017.  Achieving Privacy and Security Using QR Code by Means of Encryption Technique in ATM. 2017 Second International Conference on Recent Trends and Challenges in Computational Models (ICRTCCM). :281–285.

Smart Card has complications with validation and transmission process. Therefore, by using peeping attack, the secret code was stolen and secret filming while entering Personal Identification Number at the ATM machine. We intend to develop an authentication system to banks that protects the asset of user's. The data of a user is to be ensured that secure and isolated from the data leakage and other attacks Therefore, we propose a system, where ATM machine will have a QR code in which the information's are encrypted corresponding to the ATM machine and a mobile application in the customer's mobile which will decrypt the encoded QR information and sends the information to the server and user's details are displayed in the ATM machine and transaction can be done. Now, the user securely enters information to transfer money without risk of peeping attack in Automated Teller Machine by just scanning the QR code at the ATM by mobile application. Here, both the encryption and decryption technique are carried out by using Triple DES Algorithm (Data Encryption Standard).

2018-01-16
Alanwar, A., Shoukry, Y., Chakraborty, S., Martin, P., Tabuada, P., Srivastava, M..  2017.  PrOLoc: Resilient Localization with Private Observers Using Partial Homomorphic Encryption. 2017 16th ACM/IEEE International Conference on Information Processing in Sensor Networks (IPSN). :41–52.

This article presents PrOLoc, a localization system that combines partially homomorphic encryption with a new way of structuring the localization problem to enable emcient and accurate computation of a target's location while preserving the privacy of the observers.

Arita, S., Kozaki, S..  2017.  A Homomorphic Signature Scheme for Quadratic Polynomials. 2017 IEEE International Conference on Smart Computing (SMARTCOMP). :1–6.

Homomorphic signatures can provide a credential of a result which is indeed computed with a given function on a data set by an untrusted third party like a cloud server, when the input data are stored with the signatures beforehand. Boneh and Freeman in EUROCRYPT2011 proposed a homomorphic signature scheme for polynomial functions of any degree, however the scheme is not based on the normal short integer solution (SIS) problems as its security assumption. In this paper, we show a homomorphic signature scheme for quadratic polynomial functions those security assumption is based on the normal SIS problems. Our scheme constructs the signatures of multiplication as tensor products of the original signature vectors of input data so that homomorphism holds. Moreover, security of our scheme is reduced to the hardness of the SIS problems respect to the moduli such that one modulus is the power of the other modulus. We show the reduction by constructing solvers of the SIS problems respect to either of the moduli from any forger of our scheme.

Huang, C., Hou, C., He, L., Dai, H., Ding, Y..  2017.  Policy-Customized: A New Abstraction for Building Security as a Service. 2017 14th International Symposium on Pervasive Systems, Algorithms and Networks 2017 11th International Conference on Frontier of Computer Science and Technology 2017 Third International Symposium of Creative Computing (ISPAN-FCST-ISCC). :203–210.

Just as cloud customers have different performance requirements, they also have different security requirements for their computations in the cloud. Researchers have suggested a "security on demand" service model for cloud computing, where secure computing environment are dynamically provisioned to cloud customers according to their specific security needs. The availability of secure computing platforms is a necessary but not a sufficient solution to convince cloud customers to move their sensitive data and code to the cloud. Cloud customers need further assurance to convince them that the security measures are indeed deployed, and are working correctly. In this paper, we present Policy-Customized Trusted Cloud Service architecture with a new remote attestation scheme and a virtual machine migration protocol, where cloud customer can custom security policy of computing environment and validate whether the current computing environment meets the security policy in the whole life cycle of the virtual machine. To prove the availability of proposed architecture, we realize a prototype that support customer-customized security policy and a VM migration protocol that support customer-customized migration policy and validation based on open source Xen Hypervisor.

Feng, X., Zheng, Z., Cansever, D., Swami, A., Mohapatra, P..  2017.  A signaling game model for moving target defense. IEEE INFOCOM 2017 - IEEE Conference on Computer Communications. :1–9.

Incentive-driven advanced attacks have become a major concern to cyber-security. Traditional defense techniques that adopt a passive and static approach by assuming a fixed attack type are insufficient in the face of highly adaptive and stealthy attacks. In particular, a passive defense approach often creates information asymmetry where the attacker knows more about the defender. To this end, moving target defense (MTD) has emerged as a promising way to reverse this information asymmetry. The main idea of MTD is to (continuously) change certain aspects of the system under control to increase the attacker's uncertainty, which in turn increases attack cost/complexity and reduces the chance of a successful exploit in a given amount of time. In this paper, we go one step beyond and show that MTD can be further improved when combined with information disclosure. In particular, we consider that the defender adopts a MTD strategy to protect a critical resource across a network of nodes, and propose a Bayesian Stackelberg game model with the defender as the leader and the attacker as the follower. After fully characterizing the defender's optimal migration strategies, we show that the defender can design a signaling scheme to exploit the uncertainty created by MTD to further affect the attacker's behavior for its own advantage. We obtain conditions under which signaling is useful, and show that strategic information disclosure can be a promising way to further reverse the information asymmetry and achieve more efficient active defense.