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Corneci, Vlad-Mihai, Carabas, Costin, Deaconescu, Razvan, Tapus, Nicolae.  2019.  Adding Custom Sandbox Profiles to iOS Apps. 2019 18th RoEduNet Conference: Networking in Education and Research (RoEduNet). :1–5.
The massive adoption of mobile devices by both individuals and companies is raising many security concerns. The fact that such devices are handling sensitive data makes them a target for attackers. Many attack prevention mechanisms are deployed with a last line of defense that focuses on the containment principle. Currently, iOS treats each 3rd party application alike which may lead to security flaws. We propose a framework in which each application has a custom sandboxed environment. We investigated the current confinement architecture used by Apple and built a solution on top of it.
Johnson, R., Kiourtis, N., Stavrou, A., Sritapan, V..  2015.  Analysis of content copyright infringement in mobile application markets. 2015 APWG Symposium on Electronic Crime Research (eCrime). :1–10.

As mobile devices increasingly become bigger in terms of display and reliable in delivering paid entertainment and video content, we also see a rise in the presence of mobile applications that attempt to profit by streaming pirated content to unsuspected end-users. These applications are both paid and free and in the case of free applications, the source of funding appears to be advertisements that are displayed while the content is streamed to the device. In this paper, we assess the extent of content copyright infringement for mobile markets that span multiple platforms (iOS, Android, and Windows Mobile) and cover both official and unofficial mobile markets located across the world. Using a set of search keywords that point to titles of paid streaming content, we discovered 8,592 Android, 5,550 iOS, and 3,910 Windows mobile applications that matched our search criteria. Out of those applications, hundreds had links to either locally or remotely stored pirated content and were not developed, endorsed, or, in many cases, known to the owners of the copyrighted contents. We also revealed the network locations of 856,717 Uniform Resource Locators (URLs) pointing to back-end servers and cyber-lockers used to communicate the pirated content to the mobile application.

Teufl, P., Fitzek, A., Hein, D., Marsalek, A., Oprisnik, A., Zefferer, T..  2014.  Android encryption systems. Privacy and Security in Mobile Systems (PRISMS), 2014 International Conference on. :1-8.

The high usability of smartphones and tablets is embraced by consumers as well as the corporate and public sector. However, especially in the non-consumer area the factor security plays a decisive role for the platform-selection process. All of the current companies within the mobile device sector added a wide range of security features to the initially consumer-oriented devices (Apple, Google, Microsoft), or have dealt with security as a core feature from the beginning (RIM, now Blackerry). One of the key security features for protecting data on the device or in device backups are encryption systems, which are available in the majority of current devices. However, even under the assumption that the systems are implemented correctly, there is a wide range of parameters, specific use cases, and weaknesses that need to be considered when deploying mobile devices in security-critical environments. As the second part in a series of papers (the first part was on iOS), this work analyzes the deployment of the Android platform and the usage of its encryption systems within a security-critical context. For this purpose, Android's different encryption systems are assessed and their susceptibility to different attacks is analyzed in detail. Based on these results a workflow is presented, which supports deployment of the Android platform and usage of its encryption systems within security-critical application scenarios.

Kim, H. M., Song, H. M., Seo, J. W., Kim, H. K..  2018.  Andro-Simnet: Android Malware Family Classification Using Social Network Analysis. 2018 16th Annual Conference on Privacy, Security and Trust (PST). :1-8.

While the rapid adaptation of mobile devices changes our daily life more conveniently, the threat derived from malware is also increased. There are lots of research to detect malware to protect mobile devices, but most of them adopt only signature-based malware detection method that can be easily bypassed by polymorphic and metamorphic malware. To detect malware and its variants, it is essential to adopt behavior-based detection for efficient malware classification. This paper presents a system that classifies malware by using common behavioral characteristics along with malware families. We measure the similarity between malware families with carefully chosen features commonly appeared in the same family. With the proposed similarity measure, we can classify malware by malware's attack behavior pattern and tactical characteristics. Also, we apply community detection algorithm to increase the modularity within each malware family network aggregation. To maintain high classification accuracy, we propose a process to derive the optimal weights of the selected features in the proposed similarity measure. During this process, we find out which features are significant for representing the similarity between malware samples. Finally, we provide an intuitive graph visualization of malware samples which is helpful to understand the distribution and likeness of the malware networks. In the experiment, the proposed system achieved 97% accuracy for malware classification and 95% accuracy for prediction by K-fold cross-validation using the real malware dataset.

Liu, Xueqing.  2018.  Assisting the Development of Secure Mobile Apps with Natural Language Processing. 2018 IEEE Symposium on Visual Languages and Human-Centric Computing (VL/HCC). :279–280.
With the rapid growth of mobile devices and mobile apps, mobile has surpassed desktop and now has the largest worldwide market share [1]. While such growth brings in more opportunities, it also poses new challenges in security. Among the challenges, user privacy protection has drawn tremendous attention in recent years, especially after the Facebook-Cambridge Analytica data scandal in April 2018 [2].
Routh, Caleb, DeCrescenzo, Brandon, Roy, Swapnoneel.  2018.  Attacks and vulnerability analysis of e-mail as a password reset point. 2018 Fourth International Conference on Mobile and Secure Services (MobiSecServ). :1—5.
In this work, we perform security analysis of using an e-mail as a self-service password reset point, and exploit some of the vulnerabilities of e-mail servers' forgotten password reset paths. We perform and illustrate three different attacks on a personal Email account, using a variety of tools such as: public knowledge attainable through social media or public records to answer security questions and execute a social engineering attack, hardware available to the public to perform a man in the middle attack, and free software to perform a brute-force attack on the login of the email account. Our results expose some of the inherent vulnerabilities in using emails as password reset points. The findings are extremely relevant to the security of mobile devices since users' trend has leaned towards usage of mobile devices over desktops for Internet access.
Zhu, X., Badr, Y., Pacheco, J., Hariri, S..  2017.  Autonomic Identity Framework for the Internet of Things. 2017 International Conference on Cloud and Autonomic Computing (ICCAC). :69–79.

The Internet of Things (IoT) will connect not only computers and mobile devices, but it will also interconnect smart buildings, houses, and cities, as well as electrical grids, gas plants, and water networks, automobiles, airplanes, etc. IoT will lead to the development of a wide range of advanced information services that are pervasive, cost-effective, and can be accessed from anywhere and at any time. However, due to the exponential number of interconnected devices, cyber-security in the IoT is a major challenge. It heavily relies on the digital identity concept to build security mechanisms such as authentication and authorization. Current centralized identity management systems are built around third party identity providers, which raise privacy concerns and present a single point of failure. In addition, IoT unconventional characteristics such as scalability, heterogeneity and mobility require new identity management systems to operate in distributed and trustless environments, and uniquely identify a particular device based on its intrinsic digital properties and its relation to its human owner. In order to deal with these challenges, we present a Blockchain-based Identity Framework for IoT (BIFIT). We show how to apply our BIFIT to IoT smart homes to achieve identity self-management by end users. In the context of smart home, the framework autonomously extracts appliances signatures and creates blockchain-based identifies for their appliance owners. It also correlates appliances signatures (low level identities) and owners identifies in order to use them in authentication credentials and to make sure that any IoT entity is behaving normally.

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.

Rastogi, V., Yan Chen, Xuxian Jiang.  2014.  Catch Me If You Can: Evaluating Android Anti-Malware Against Transformation Attacks. Information Forensics and Security, IEEE Transactions on. 9:99-108.

Mobile malware threats (e.g., on Android) have recently become a real concern. In this paper, we evaluate the state-of-the-art commercial mobile anti-malware products for Android and test how resistant they are against various common obfuscation techniques (even with known malware). Such an evaluation is important for not only measuring the available defense against mobile malware threats, but also proposing effective, next-generation solutions. We developed DroidChameleon, a systematic framework with various transformation techniques, and used it for our study. Our results on 10 popular commercial anti-malware applications for Android are worrisome: none of these tools is resistant against common malware transformation techniques. In addition, a majority of them can be trivially defeated by applying slight transformation over known malware with little effort for malware authors. Finally, in light of our results, we propose possible remedies for improving the current state of malware detection on mobile devices.

Hassan, M.M., Hossain, M.A., Al-Qurishi, M..  2014.  Cloud-based mobile IPTV terminal for video surveillance. Advanced Communication Technology (ICACT), 2014 16th International Conference on. :876-880.

Surveillance video streams monitoring is an important task that the surveillance operators usually carry out. The distribution of video surveillance facilities over multiple premises and the mobility of surveillance users requires that they are able to view surveillance video seamlessly from their mobile devices. In order to satisfy this requirement, we propose a cloud-based IPTV (Internet Protocol Television) solution that leverages the power of cloud infrastructure and the benefits of IPTV technology to seamlessly deliver surveillance video content on different client devices anytime and anywhere. The proposed mechanism also supports user-controlled frame rate adjustment of video streams and sharing of these streams with other users. In this paper, we describe the overall approach of this idea, address and identify key technical challenges for its practical implementation. In addition, initial experimental results were presented to justify the viability of the proposed cloud-based IPTV surveillance framework over the traditional IPTV surveillance approach.

Cailleux, L., Bouabdallah, A., Bonnin, J.-M..  2014.  A confident email system based on a new correspondence model. Advanced Communication Technology (ICACT), 2014 16th International Conference on. :489-492.

Despite all the current controversies, the success of the email service is still valid. The ease of use of its various features contributed to its widespread adoption. In general, the email system provides for all its users the same set of features controlled by a single monolithic policy. Such solutions are efficient but limited because they grant no place for the concept of usage which denotes a user's intention of communication: private, professional, administrative, official, military. The ability to efficiently send emails from mobile devices creates new interesting opportunities. We argue that the context (location, time, device, operating system, access network...) of the email sender appears as a new dimension we have to take into account to complete the picture. Context is clearly orthogonal to usage because a same usage may require different features depending of the context. It is clear that there is no global policy meeting requirements of all possible usages and contexts. To address this problem, we propose to define a correspondence model which for a given usage and context allows to derive a correspondence type encapsulating the exact set of required features. With this model, it becomes possible to define an advanced email system which may cope with multiple policies instead of a single monolithic one. By allowing a user to select the exact policy coping with her needs, we argue that our approach reduces the risk-taking allowing the email system to slide from a trusted one to a confident one.

Moon, J., Lee, Y., Yang, H., Song, T., Won, D..  2018.  Cryptanalysis of a privacy-preserving and provable user authentication scheme for wireless sensor networks based on Internet of Things security. 2018 International Conference on Information Networking (ICOIN). :432–437.
User authentication in wireless sensor networks is more complex than normal networks due to sensor network characteristics such as unmanned operation, limited resources, and unreliable communication. For this reason, various authentication protocols have been presented to provide secure and efficient communication. In 2017, Wu et al. presented a provable and privacy-preserving user authentication protocol for wireless sensor networks. Unfortunately, we found that Wu et al.'s protocol was still vulnerable against user impersonation attack, and had a problem in the password change phase. We show how an attacker can impersonate an other user and why the password change phase is ineffective.
Salman, A., Elhajj, I.H., Chehab, A., Kayssi, A..  2014.  DAIDS: An Architecture for Modular Mobile IDS. Advanced Information Networking and Applications Workshops (WAINA), 2014 28th International Conference on. :328-333.

The popularity of mobile devices and the enormous number of third party mobile applications in the market have naturally lead to several vulnerabilities being identified and abused. This is coupled with the immaturity of intrusion detection system (IDS) technology targeting mobile devices. In this paper we propose a modular host-based IDS framework for mobile devices that uses behavior analysis to profile applications on the Android platform. Anomaly detection can then be used to categorize malicious behavior and alert users. The proposed system accommodates different detection algorithms, and is being tested at a major telecom operator in North America. This paper highlights the architecture, findings, and lessons learned.

Liu, Ying, He, Qiang, Zheng, Dequan, Zhang, Mingwei, Chen, Feifei, Zhang, Bin.  2019.  Data Caching Optimization in the Edge Computing Environment. 2019 IEEE International Conference on Web Services (ICWS). :99–106.

With the rapid increase in the use of mobile devices in people's daily lives, mobile data traffic is exploding in recent years. In the edge computing environment where edge servers are deployed around mobile users, caching popular data on edge servers can ensure mobile users' fast access to those data and reduce the data traffic between mobile users and the centralized cloud. Existing studies consider the data cache problem with a focus on the reduction of network delay and the improvement of mobile devices' energy efficiency. In this paper, we attack the data caching problem in the edge computing environment from the service providers' perspective, who would like to maximize their venues of caching their data. This problem is complicated because data caching produces benefits at a cost and there usually is a trade-off in-between. In this paper, we formulate the data caching problem as an integer programming problem, and maximizes the revenue of the service provider while satisfying a constraint for data access latency. Extensive experiments are conducted on a real-world dataset that contains the locations of edge servers and mobile users, and the results reveal that our approach significantly outperform the baseline approaches.

Jindal, M., Dave, M..  2014.  Data security protocol for cloudlet based architecture. Recent Advances and Innovations in Engineering (ICRAIE), 2014. :1-5.

Mobile cloud computing is a combination of mobile computing and cloud computing that provides a platform for mobile users to offload heavy tasks and data on the cloud, thus, helping them to overcome the limitations of their mobile devices. However, while utilizing the mobile cloud computing technology users lose physical control of their data; this ultimately calls for the need of a data security protocol. Although, numerous such protocols have been proposed,none of them consider a cloudlet based architecture. A cloudlet is a reliable, resource-rich computer/cluster which is well-connected to the internet and is available to nearby mobile devices. In this paper, we propose a data security protocol for a distributed cloud architecture having cloudlet integrated with the base station, using the property of perfect forward secrecy. Our protocol not only protects data from any unauthorized user, but also prevents exposure of data to the cloud owner.

J. J. Li, P. Abbate, B. Vega.  2015.  "Detecting Security Threats Using Mobile Devices". 2015 IEEE International Conference on Software Quality, Reliability and Security - Companion. :40-45.

In our previous work [1], we presented a study of using performance escalation to automatic detect Distributed Denial of Service (DDoS) types of attacks. We propose to enhance the work of security threat detection by using mobile phones as the detector to identify outliers of normal traffic patterns as threats. The mobile solution makes detection portable to any services. This paper also shows that the same detection method works for advanced persistent threats.

Ledbetter, W., Glisson, W., McDonald, T., Andel, T., Grispos, G., Choo, K..  2018.  Digital Blues: An Investigation Into the Use of Bluetooth Protocols. 2018 17th IEEE International Conference On Trust, Security And Privacy In Computing And Communications/ 12th IEEE International Conference On Big Data Science And Engineering (TrustCom/BigDataSE). :498–503.
The proliferation of Bluetooth mobile device communications into all aspects of modern society raises security questions by both academicians and practitioners. This environment prompted an investigation into the real-world use of Bluetooth protocols along with an analysis of documented security attacks. The experiment discussed in this paper collected data for one week in a local coffee shop. The data collection took about an hour each day and identified 478 distinct devices. The contribution of this research is two-fold. First, it provides insight into real-world Bluetooth protocols that are being utilized by the general public. Second, it provides foundational research that is necessary for future Bluetooth penetration testing research.
Zhang, H., Chen, L., Liu, Q..  2018.  Digital Forensic Analysis of Instant Messaging Applications on Android Smartphones. 2018 International Conference on Computing, Networking and Communications (ICNC). :647–651.

In this paper, we discuss the digital forensic procedure and techniques for analyzing the local artifacts from four popular Instant Messaging applications in Android. As part of our findings, the user chat messages details and contacts were investigated for each application. By using two smartphones with different brands and the latest Android operating systems as experimental objects, we conducted digital investigations in a forensically sound manner. We summarize our findings regarding the different Instant Messaging chat modes and the corresponding encryption status of artifacts for each of the four applications. Our findings can be helpful to many mobile forensic investigations. Additionally, these findings may present values to Android system developers, Android mobile app developers, mobile security researchers as well as mobile users.

Pacheco, J., Zhu, X., Badr, Y., Hariri, S..  2017.  Enabling Risk Management for Smart Infrastructures with an Anomaly Behavior Analysis Intrusion Detection System. 2017 IEEE 2nd International Workshops on Foundations and Applications of Self* Systems (FAS*W). :324–328.

The Internet of Things (IoT) connects not only computers and mobile devices, but it also interconnects smart buildings, homes, and cities, as well as electrical grids, gas, and water networks, automobiles, airplanes, etc. However, IoT applications introduce grand security challenges due to the increase in the attack surface. Current security approaches do not handle cybersecurity from a holistic point of view; hence a systematic cybersecurity mechanism needs to be adopted when designing IoTbased applications. In this work, we present a risk management framework to deploy secure IoT-based applications for Smart Infrastructures at the design time and the runtime. At the design time, we propose a risk management method that is appropriate for smart infrastructures. At the design time, our framework relies on the Anomaly Behavior Analysis (ABA) methodology enabled by the Autonomic Computing paradigm and an intrusion detection system to detect any threat that can compromise IoT infrastructures by. Our preliminary experimental results show that our framework can be used to detect threats and protect IoT premises and services.

Jin, Yong, Tomoishi, Masahiko.  2019.  Encrypted QR Code Based Optical Challenge-Response Authentication by Mobile Devices for Mounting Concealed File System. 2019 IEEE 43rd Annual Computer Software and Applications Conference (COMPSAC). 2:676–681.
Nowadays mobile devices have become the majority terminals used by people for social activities so that carrying business data and private information in them have become normal. Accordingly, the risk of data related cyber attacks has become one of the most critical security concerns. The main purpose of this work is to mitigate the risk of data breaches and damages caused by malware and the lost of mobile devices. In this paper, we propose an encrypted QR code based optical challenge-response authentication by mobile devices for mounting concealed file systems. The concealed file system is basically invisible to the users unless being successfully mounted. The proposed authentication scheme practically applies cryptography and QR code technologies to challenge-response scheme in order to secure the concealed file system. The key contribution of this work is to clarify a possibility of a mounting authentication scheme involving two mobile devices using a special optical communication way (QR code exchanges) which can be realizable without involving any network accesses. We implemented a prototype system and based on the preliminary feature evaluations results we confirmed that encrypted QR code based optical challenge-response is possible between a laptop and a smart phone and it can be applied to authentication for mounting concealed file systems.
Shen, Y., Wang, H..  2017.  Enhancing data security of iOS client by encryption algorithm. 2017 IEEE 2nd Advanced Information Technology, Electronic and Automation Control Conference (IAEAC). :366–370.

iOS devices are steadily obtaining popularity of the majority of users because of its some unique advantages in recent years. They can do many things that have been done on a desktop computer or laptop. With the increase in the use of mobile devices by individuals, organizations and government, there are many problems with information security especially some sensitive data related to users. As we all known, encryption algorithm play a significant role in data security. In order to prevent data being intercepted and being leaked during communication, in this paper, we adopted DES encryption algorithm that is fast, simple and suitable for large amounts of data of encryption to encrypt the data of iOS client and adopted the ECC encryption algorithms that was used to overcome the shortcoming of exchanging keys in a securing way before communications. In addition, we should also consider the application isolation and security mechanism of iOS that these features also protect the data securing to some extent. Namely, we propose an encryption algorithm combined the strengths of DES and ECC and make full use of the advantages of hybrid algorithm. Then, we tested and evaluated the performances of the suggested cryptography mechanism within the mobile platform of iOS. The results show that the algorithm has fairly efficiency in practical applications and strong anti-attack ability and it also improves the security and efficiency in data transmission.

Silva, F., Castillo-Lema, J., Neto, A., Silva, F., Rosa, P., Corujo, D., Guimaraes, C., Aguiar, R..  2014.  Entity title architecture extensions towards advanced quality-oriented mobility control capabilities. Computers and Communication (ISCC), 2014 IEEE Symposium on. :1-6.

The emergence of new technologies, in addition with the popularization of mobile devices and wireless communication systems, demands a variety of requirements that current Internet is not able to comply adequately. In this scenario, the innovative information-centric Entity Title Architecture (ETArch), a Future Internet (FI) clean slate approach, was design to efficiently cope with the increasing demand of beyond-IP networking services. Nevertheless, despite all ETArch capabilities, it was not projected with reliable networking functions, which limits its operability in mobile multimedia networking, and will seriously restrict its scope in Future Internet scenarios. Therefore, our work extends ETArch mobility control with advanced quality-oriented mobility functions, to deploy mobility prediction, Point of Attachment (PoA) decision and handover setup meeting both session quality requirements of active session flows and current wireless quality conditions of neighbouring PoA candidates. The effectiveness of the proposed additions were confirmed through a preliminary evaluation carried out by MATLAB, in which we have considered distinct applications scenario, and showed that they were able to outperform the most relevant alternative solutions in terms of performance and quality of service.

Antal, M., Szabó, L. Z..  2015.  An Evaluation of One-Class and Two-Class Classification Algorithms for Keystroke Dynamics Authentication on Mobile Devices. 2015 20th International Conference on Control Systems and Computer Science. :343–350.

In this paper we study keystroke dynamics as an authentication mechanism for touch screen based devices. The authentication process decides whether the identity of a given person is accepted or rejected. This can be easily implemented by using a two-class classifier which operates with the help of positive samples (belonging to the authentic person) and negative ones. However, collecting negative samples is not always a viable option. In such cases a one-class classification algorithm can be used to characterize the target class and distinguish it from the outliers. We implemented an authentication test-framework that is capable of working with both one-class and two-class classification algorithms. The framework was evaluated on our dataset containing keystroke samples from 42 users, collected from touch screen-based Android devices. Experimental results yield an Equal Error Rate (EER) of 3% (two-class) and 7% (one-class) respectively.

Kellner, Ansgar, Horlboge, Micha, Rieck, Konrad, Wressnegger, Christian.  2019.  False Sense of Security: A Study on the Effectivity of Jailbreak Detection in Banking Apps. 2019 IEEE European Symposium on Security and Privacy (EuroS P). :1—14.
People increasingly rely on mobile devices for banking transactions or two-factor authentication (2FA) and thus trust in the security provided by the underlying operating system. Simultaneously, jailbreaks gain tremendous popularity among regular users for customizing their devices. In this paper, we show that both do not go well together: Jailbreaks remove vital security mechanisms, which are necessary to ensure a trusted environment that allows to protect sensitive data, such as login credentials and transaction numbers (TANs). We find that all but one banking app, available in the iOS App Store, can be fully compromised by trivial means without reverse-engineering, manipulating the app, or other sophisticated attacks. Even worse, 44% of the banking apps do not even try to detect jailbreaks, revealing the prevalent, errant trust in the operating system's security. This study assesses the current state of security of banking apps and pleads for more advanced defensive measures for protecting user data.
Garbo, A., Quer, S..  2018.  A Fast MPEG’s CDVS Implementation for GPU Featured in Mobile Devices. IEEE Access. 6:52027—52046.
The Moving Picture Experts Group's Compact Descriptors for Visual Search (MPEG's CDVS) intends to standardize technologies in order to enable an interoperable, efficient, and cross-platform solution for internet-scale visual search applications and services. Among the key technologies within CDVS, we recall the format of visual descriptors, the descriptor extraction process, and the algorithms for indexing and matching. Unfortunately, these steps require precision and computation accuracy. Moreover, they are very time-consuming, as they need running times in the order of seconds when implemented on the central processing unit (CPU) of modern mobile devices. In this paper, to reduce computation times and maintain precision and accuracy, we re-design, for many-cores embedded graphical processor units (GPUs), all main local descriptor extraction pipeline phases of the MPEG's CDVS standard. To reach this goal, we introduce new techniques to adapt the standard algorithm to parallel processing. Furthermore, to reduce memory accesses and efficiently distribute the kernel workload, we use new approaches to store and retrieve CDVS information on proper GPU data structures. We present a complete experimental analysis on a large and standard test set. Our experiments show that our GPU-based approach is remarkably faster than the CPU-based reference implementation of the standard, and it maintains a comparable precision in terms of true and false positive rates.