Biblio
Network security and data confidentiality of transmitted information are among the non-functional requirements of industrial wireless sensor networks (IWSNs) in addition to latency, reliability and energy efficiency requirements. Physical layer security techniques are promising solutions to assist cryptographic methods in the presence of an eavesdropper in IWSN setups. In this paper, we propose a physical layer security scheme, which is based on both insertion of an random error vector to forward error correction (FEC) codewords and transmission over decentralized relay nodes. Reed-Solomon and Golay codes are selected as FEC coding schemes and the security performance of the proposed model is evaluated with the aid of decoding error probability of an eavesdropper. The results show that security level is highly based on the location of the eavesdropper and secure communication can be achieved when some of channels between eavesdropper and relay nodes are significantly noisier.
Industrial networks are the cornerstone of modern industrial control systems. Performing security checks of industrial communication processes helps detect unknown risks and vulnerabilities. Fuzz testing is a widely used method for performing security checks that takes advantage of automation. However, there is a big challenge to carry out security checks on industrial network due to the increasing variety and complexity of industrial communication protocols. In this case, existing approaches usually take a long time to model the protocol for generating test cases, which is labor-intensive and time-consuming. This becomes even worse when the target protocol is stateful. To help in addressing this problem, we employed a deep learning model to learn the structures of protocol frames and deal with the temporal features of stateful protocols. We propose a fuzzing framework named SeqFuzzer which automatically learns the protocol frame structures from communication traffic and generates fake but plausible messages as test cases. For proving the usability of our approach, we applied SeqFuzzer to widely-used Ethernet for Control Automation Technology (EtherCAT) devices and successfully detected several security vulnerabilities.
The increase of the digitalization taking place in various industrial domains is leading developers towards the design and implementation of more and more complex networked control systems (NCS) supported by Wireless Sensor Networks (WSN). This naturally raises new challenges for the current WSN technology, namely in what concerns improved guarantees of technical aspects such as real-time communications together with safe and secure transmissions. Notably, in what concerns security aspects, several cryptographic protocols have been proposed. Since the design of these protocols is usually error-prone, security breaches can still be exposed and MALICIOUSly exploited unless they are rigorously analyzed and verified. In this paper we formally verify, using ProVerif, three cryptographic protocols used in WSN, regarding the security properties of secrecy and authenticity. The security analysis performed in this paper is more robust than the ones performed in related work. Our contributions involve analyzing protocols that were modeled considering an unbounded number of participants and actions, and also the use of a hierarchical system to classify the authenticity results. Our verification shows that the three analyzed protocols guarantee secrecy, but can only provide authenticity in specific scenarios.
In this paper, we show how practical the little theorem of witness functions is in detecting security flaws in some categories of cryptographic protocols. We convey a formal analysis of the Needham-Schroeder symmetric-key protocol in the theory of witness functions. We show how it helps to warn about a security vulnerability in a given step of this protocol where the value of security of a sensitive ticket in a sent message unexpectedly decreases compared with its value when received. This vulnerability may be exploited by an intruder to mount a replay attack as described by Denning and Sacco.
As trust becomes increasingly important in the software domain. Due to its complex composite concept, people face great challenges, especially in today's dynamic and constantly changing internet technology. In addition, measuring the software trustworthiness correctly and effectively plays a significant role in gaining users trust in choosing different software. In the context of security, trust is previously measured based on the vulnerability time occurrence to predict the total number of vulnerabilities or their future occurrence time. In this study, we proposed a new unified index called "loss speed index" that integrates the most important variables of software security such as vulnerability occurrence time, number and severity loss, which are used to evaluate the overall software trust measurement. Based on this new definition, a new model called software trustworthy security growth model (STSGM) has been proposed. This paper also aims at filling the gap by addressing the severity of vulnerabilities and proposed a vulnerability severity prediction model, the results are further evaluated by STSGM to estimate the future loss speed index. Our work has several features such as: (1) It is used to predict the vulnerability severity/type in future, (2) Unlike traditional evaluation methods like expert scoring, our model uses historical data to predict the future loss speed of software, (3) The loss metric value is used to evaluate the risk associated with different software, which has a direct impact on software trustworthiness. Experiments performed on real software vulnerability datasets and its results are analyzed to check the correctness and effectiveness of the proposed model.
Cloud Computing is the most suitable environment for the collaboration of multiple organizations via its multi-tenancy architecture. However, due to the distributed management of policies within these collaborations, they may contain several anomalies, such as conflicts and redundancies, which may lead to both safety and availability problems. On the other hand, current cloud computing solutions do not offer verification tools to manage access control policies. In this paper, we propose a cloud policy verification service (CPVS), that facilitates to users the management of there own security policies within Openstack cloud environment. Specifically, the proposed cloud service offers a policy verification approach to dynamically choose the adequate policy using Aspect-Oriented Finite State Machines (AO-FSM), where pointcuts and advices are used to adopt Domain-Specific Language (DSL) state machine artifacts. The pointcuts define states' patterns representing anomalies (e.g., conflicts) that may occur in a security policy, while the advices define the actions applied at the selected pointcuts to remove the anomalies. In order to demonstrate the efficiency of our approach, we provide time and space complexities. The approach was implemented as middleware service within Openstack cloud environment. The implementation results show that the middleware can detect and resolve different policy anomalies in an efficient manner.
Since cyber-physical systems are inherently vulnerable to information leaks, software architects need to reason about security policies to define desired and undesired information flow through a system. The microservice architectural style requires the architects to refine a macro-level security policy into micro-level policies for individual microservices. However, when policies are refined in an ill-formed way, information leaks can emerge on composition of microservices. Related approaches to prevent such leaks do not take into account characteristics of cyber-physical systems like real-time behavior or message passing communication. In this paper, we enable the refinement and verification of information-flow security policies for cyber-physical microservice architectures. We provide architects with a set of well-formedness rules for refining a macro-level policy in a way that enforces its security restrictions. Based on the resulting micro-level policies, we present a verification technique to check if the real-time message passing of microservices is secure. In combination, our contributions prevent information leaks from emerging on composition. We evaluate the accuracy of our approach using an extension of the CoCoME case study.
Despite the wide of range of research and technologies that deal with the problem of routing in computer networks, there remains a gap between the level of network hardware administration and the level of business requirements and constraints. Not much has been accomplished in literature in order to have a direct enforcement of such requirements on the network. This paper presents a new solution in specifying and directly enforcing security policies to control the routing configuration in a software-defined network by using Row-Level Security checks which enable fine-grained security policies on individual rows in database tables. We show, as a first step, how a specific class of such policies, namely multilevel security policies, can be enforced on a database-defined network, which presents an abstraction of a network's configuration as a set of database tables. We show that such policies can be used to control the flow of data in the network either in an upward or downward manner.
Security policy is widely used in network management systems to ensure network security. It is necessary to detect and resolve conflicts in security policies. This paper analyzes the shortcomings of existing security policy conflict detection methods and proposes a B+ tree-based security policy conflict detection method. First, the security policy is dimensioned to make each attribute corresponds to one dimension. Then, a layer of B+ tree index is constructed at each dimension level. Each rule will be uniquely mapped by multiple layers of nested indexes. This method can greatly improve the efficiency of conflict detection. The experimental results show that the method has very stable performance which can effectively prevent conflicts, the type of policy conflict can be detected quickly and accurately.
Increasingly organizations are collecting ever larger amounts of data to build complex data analytics, machine learning and AI models. Furthermore, the data needed for building such models may be unstructured (e.g., text, image, and video). Hence such data may be stored in different data management systems ranging from relational databases to newer NoSQL databases tailored for storing unstructured data. Furthermore, data scientists are increasingly using programming languages such as Python, R etc. to process data using many existing libraries. In some cases, the developed code will be automatically executed by the NoSQL system on the stored data. These developments indicate the need for a data security and privacy solution that can uniformly protect data stored in many different data management systems and enforce security policies even if sensitive data is processed using a data scientist submitted complex program. In this paper, we introduce our vision for building such a solution for protecting big data. Specifically, our proposed system system allows organizations to 1) enforce policies that control access to sensitive data, 2) keep necessary audit logs automatically for data governance and regulatory compliance, 3) sanitize and redact sensitive data on-the-fly based on the data sensitivity and AI model needs, 4) detect potentially unauthorized or anomalous access to sensitive data, 5) automatically create attribute-based access control policies based on data sensitivity and data type.
Despite corporate cyber intrusions attracting all the attention, privacy breaches that we, as ordinary users, should be worried about occur every day without any scrutiny. Smartphones, a household item, have inadvertently become a major enabler of privacy breaches. Smartphone platforms use permission systems to regulate access to sensitive resources. These permission systems, however, lack the ability to understand users’ privacy expectations leaving a significant gap between how permission models behave and how users would want the platform to protect their sensitive data. This dissertation provides an in-depth analysis of how users make privacy decisions in the context of Smartphones and how platforms can accommodate user’s privacy requirements systematically. We first performed a 36-person field study to quantify how often applications access protected resources when users are not expecting it. We found that when the application requesting the permission is running invisibly to the user, they are more likely to deny applications access to protected resources. At least 80% of our participants would have preferred to prevent at least one permission request. To explore the feasibility of predicting user’s privacy decisions based on their past decisions, we performed a longitudinal 131-person field study. Based on the data, we built a classifier to make privacy decisions on the user’s behalf by detecting when the context has changed and inferring privacy preferences based on the user’s past decisions. We showed that our approach can accurately predict users’ privacy decisions 96.8% of the time, which is an 80% reduction in error rate compared to current systems. Based on these findings, we developed a custom Android version with a contextually aware permission model. The new model guards resources based on user’s past decisions under similar contextual circumstances. We performed a 38-person field study to measure the efficiency and usability of the new permission model. Based on exit interviews and 5M data points, we found that the new system is effective in reducing the potential violations by 75%. Despite being significantly more restrictive over the default permission systems, participants did not find the new model to cause any usability issues in terms of application functionality.
In monolithic operating system (OS), any error of system software can be exploit to destroy the whole system. The situation becomes much more severe in cloud environment, when the kernel and the hypervisor share the same address space. The security of guest Virtual Machines (VMs), both sensitive data and vital code, can no longer be guaranteed, once the hypervisor is compromised. Therefore, it is essential to deploy some security approaches to secure VMs, regardless of the hypervisor is safe or not. Some approaches propose microhypervisor reducing attack surface, or a new software requiring a higher privilege level than hypervisor. In this paper, we propose a novel approach, named HyperPS, which separates the fundamental and crucial privilege into a new trusted environment in order to monitor hypervisor. A pivotal condition for HyperPS is that hypervisor must not be allowed to manipulate any security-sensitive system resources, such as page tables, system control registers, interaction between VM and hypervisor as well as VM memory mapping. Besides, HyperPS proposes a trusted environment which does not rely on any higher privilege than the hypervisor. We have implemented a prototype for KVM hypervisor on x86 platform with multiple VMs running Linux. KVM with HyperPS can be applied to current commercial cloud computing industry with portability. The security analysis shows that this approach can provide effective monitoring against attacks, and the performance evaluation confirms the efficiency of HyperPS.
Agile methods frequently have difficulties with qualities, often specifying quality requirements as stories, e.g., "As a user, I need a safe and secure system." Such projects will generally schedule some capability releases followed by safety and security releases, only to discover user-developer misunderstandings and unsecurable agile code, leading to project failure. Very large agile projects also have further difficulties with project velocity and scalability. Examples are trying to use daily standup meetings, 2-week sprints, shared tacit knowledge vs. documents, and dealing with user-developer misunderstandings. At USC, our Parallel Agile, Executable Architecture research project shows some success at mid-scale (50 developers). We also examined several large (hundreds of developers) TRW projects that had succeeded with rapid, high-quality development. The paper elaborates on their common Critical Quality Factors: a concurrent 3-team approach, an empowered Keeper of the Project Vision, and a management approach emphasizing qualities.
Vehicular Ad-hoc Network (VANET) can provide vehicle to vehicle (V2V) and vehicle to infrastructure (V2I) communications for efficient and safe transportation. The vehicles features high mobility, thus undergoing frequent handovers when they are moving, which introduces the significant overload on the network entities. To address the problem, the distributed mobility management (DMM) protocol for next generation mobile network has been proposed, which can be well combined with VANETs. Although the existing DMM solutions can guarantee the smooth handovers of vehicles, the security has not been fully considered in the mobility management. Moreover, the most of existing schemes cannot support group communication scenario. In this paper, we propose an efficient and secure group mobility management scheme based on the blockchain. Specifically, to reduce the handover latency and signaling cost during authentication, aggregate message authentication code (AMAC) and one-time password (OTP) are adopted. The security analysis and the performance evaluation results show that the proposed scheme can not only enhance the security functionalities but also support fast handover authentication.