Dynamic Risk Analyses and Dependency-Aware Root Cause Model for Critical Infrastructures

in International Conference on Critical Information Infrastructures Security (2016)

Critical Infrastructures are known for their complexity and the strong interdependencies between the various components. As a result, cascading effects can have devastating consequences, while foreseeing ... [more ▼]

Critical Infrastructures are known for their complexity and the strong interdependencies between the various components. As a result, cascading effects can have devastating consequences, while foreseeing the overall impact of a particular incident is not straight-forward at all and goes beyond performing a simple risk analysis. This work presents a graph-based approach for conducting dynamic risk analyses, which are programmatically generated from a threat model and an inventory of assets. In contrast to traditional risk analyses, they can be kept automatically up-to-date and show the risk currently faced by a system in real-time. The concepts are applied to and validated in the context of the smart grid infrastructure currently being deployed in Luxembourg. [less ▲]

Suspicious Electric Consumption Detection Based on Multi-Profiling Using Live Machine Learning

in 2015 IEEE International Conference on Smart Grid Communications (SmartGridComm) (2015, November)

The transition from today’s electricity grid to the so-called smart grid relies heavily on the usage of modern information and communication technology to enable advanced features like two-way ... [more ▼]

The transition from today’s electricity grid to the so-called smart grid relies heavily on the usage of modern information and communication technology to enable advanced features like two-way communication, an automated control of devices, and automated meter reading. The digital backbone of the smart grid opens the door for advanced collecting, monitoring, and processing of customers’ energy consumption data. One promising approach is the automatic detection of suspicious consumption values, e.g., due to physically or digitally manipulated data or damaged devices. However, detecting suspicious values in the amount of meter data is challenging, especially because electric consumption heavily depends on the context. For instance, a customers energy consumption profile may change during vacation or weekends compared to normal working days. In this paper we present an advanced software monitoring and alerting system for suspicious consumption value detection based on live machine learning techniques. Our proposed system continuously learns context-dependent consumption profiles of customers, e.g., daily, weekly, and monthly profiles, classifies them and selects the most appropriate one according to the context, like date and weather. By learning not just one but several profiles per customer and in addition taking context parameters into account, our approach can minimize false alerts (low false positive rate). We evaluate our approach in terms of performance (live detection) and accuracy based on a data set from our partner, Creos Luxembourg S.A., the electricity grid operator in Luxembourg. [less ▲]

SoSPa: A System of Security Design Patterns for Systematically Engineering Secure Systems

in Proceedings ACM/IEEE 18th International Conference on Model Driven Engineering Languages and Systems (2015, October)

Model-Driven Security (MDS) for secure systems development still has limitations to be more applicable in practice. A recent systematic review of MDS shows that current MDS approaches have not dealt with ... [more ▼]

Model-Driven Security (MDS) for secure systems development still has limitations to be more applicable in practice. A recent systematic review of MDS shows that current MDS approaches have not dealt with multiple security concerns systematically. Besides, catalogs of security patterns which can address multiple security concerns have not been applied efficiently. This paper presents an MDS approach based on a unified System of Security design Patterns (SoSPa). In SoSPa, security design patterns are collected, specified as reusable aspect models to form a coherent system of them that guides developers in systematically addressing multiple security concerns. SoSPa consists of not only interrelated security design patterns but also a refinement process towards their application. We applied SoSPa to design the security of crisis management systems. The result shows that multiple security concerns in the case study have been addressed by systematically integrating different security solutions. [less ▲]

An Extensive Systematic Review on the Model-Driven Development of Secure Systems

in Information & Software Technology (2015), 68(December 2015), 62-81

Context: Model-Driven Security (MDS) is as a specialised Model-Driven Engineering research area for supporting the development of secure systems. Over a decade of research on MDS has resulted in a large ... [more ▼]

Context: Model-Driven Security (MDS) is as a specialised Model-Driven Engineering research area for supporting the development of secure systems. Over a decade of research on MDS has resulted in a large number of publications. Objective: To provide a detailed analysis of the state of the art in MDS, a systematic literature review (SLR) is essential. Method: We conducted an extensive SLR on MDS. Derived from our research questions, we designed a rigorous, extensive search and selection process to identify a set of primary MDS studies that is as complete as possible. Our three-pronged search process consists of automatic searching, manual searching, and snowballing. After discovering and considering more than thousand relevant papers, we identified, strictly selected, and reviewed 108 MDS publications. Results: The results of our SLR show the overall status of the key artefacts of MDS, and the identified primary MDS studies. E.g. regarding security modelling artefact, we found that developing domain-specific languages plays a key role in many MDS approaches. The current limitations in each MDS artefact are pointed out and corresponding potential research directions are suggested. Moreover, we categorise the identified primary MDS studies into 5 significant MDS studies, and other emerging or less common MDS studies. Finally, some trend analyses of MDS research are given. Conclusion: Our results suggest the need for addressing multiple security concerns more systematically and simultaneously, for tool chains supporting the MDS development cycle, and for more empirical studies on the application of MDS methodologies. To the best of our knowledge, this SLR is the first in the field of Software Engineering that combines a snowballing strategy with database searching. This combination has delivered an extensive literature study on MDS. [less ▲]

Beyond Discrete Modeling: A Continuous and Efficient Model for IoT

in Lethbridge, Timothy; Cabot, Jordi; Egyed, Alexander (Eds.) 2015 ACM/IEEE 18th International Conference on Model Driven Engineering Languages and Systems (MODELS) (2015, September)

Internet of Things applications analyze our past habits through sensor measures to anticipate future trends. To yield accurate predictions, intelligent systems not only rely on single numerical values ... [more ▼]

Internet of Things applications analyze our past habits through sensor measures to anticipate future trends. To yield accurate predictions, intelligent systems not only rely on single numerical values, but also on structured models aggregated from different sensors. Computation theory, based on the discretization of observable data into timed events, can easily lead to millions of values. Time series and similar database structures can efficiently index the mere data, but quickly reach computation and storage limits when it comes to structuring and processing IoT data. We propose a concept of continuous models that can handle high-volatile IoT data by defining a new type of meta attribute, which represents the continuous nature of IoT data. On top of traditional discrete object-oriented modeling APIs, we enable models to represent very large sequences of sensor values by using mathematical polynomials. We show on various IoT datasets that this significantly improves storage and reasoning efficiency. [less ▲]

ApkCombiner: Combining Multiple Android Apps to Support Inter-App Analysis

in International Conference on ICT Systems Security and Privacy Protection (SEC 2015) (2015, May)

Adaptive Blurring of Sensor Data to balance Privacy and Utility for Ubiquitous Services

in The 30th Annual ACM Symposium on Applied Computing (2015, April)

Given the trend towards mobile computing, the next generation of ubiquitous “smart” services will have to continuously analyze surrounding sensor data. More than ever, such services will rely on data ... [more ▼]

Given the trend towards mobile computing, the next generation of ubiquitous “smart” services will have to continuously analyze surrounding sensor data. More than ever, such services will rely on data potentially related to personal activities to perform their tasks, e.g. to predict urban traffic or local weather conditions. However, revealing personal data inevitably entails privacy risks, especially when data is shared with high precision and frequency. For example, by analyzing the precise electric consumption data, it can be inferred if a person is currently at home, however this can empower new services such as a smart heating system. Access control (forbid or grant access) or anonymization techniques are not able to deal with such trade-off because whether they completely prohibit access to data or lose source traceability. Blurring techniques, by tuning data quality, offer a wide range of trade-offs between privacy and utility for services. However, the amount of ubiquitous services and their data quality requirements lead to an explosion of possible configurations of blurring algorithms. To manage this complexity, in this paper we propose a platform that automatically adapts (at runtime) blurring components between data owners and data consumers (services). The platform searches the optimal trade-off between service utility and privacy risks using multi-objective evolutionary algorithms to adapt the underlying communication platform. We evaluate our approach on a sensor network gateway and show its suitability in terms of i) effectiveness to find an appropriate solution, ii) efficiency and scalability. [less ▲]

IccTA: Detecting Inter-Component Privacy Leaks in Android Apps

in 2015 IEEE/ACM 37th IEEE International Conference on Software Engineering (ICSE 2015) (2015)

Shake Them All is a popular "Wallpaper" application exceeding millions of downloads on Google Play. At installation, this application is given permission to (1) access the Internet (for updating ... [more ▼]

Shake Them All is a popular "Wallpaper" application exceeding millions of downloads on Google Play. At installation, this application is given permission to (1) access the Internet (for updating wallpapers) and (2) use the device microphone (to change background following noise changes). With these permissions, the application could silently record user conversations and upload them remotely. To give more confidence about how Shake Them All actually processes what it records, it is necessary to build a precise analysis tool that tracks the flow of any sensitive data from its source point to any sink, especially if those are in different components. Since Android applications may leak private data carelessly or maliciously, we propose IccTA, a static taint analyzer to detect privacy leaks among components in Android applications. IccTA goes beyond state-of-the-art approaches by supporting inter-component detection. By propagating context information among components, IccTA improves the precision of the analysis. IccTA outperforms existing tools on two benchmarks for ICC-leak detectors: DroidBench and ICC-Bench. Moreover, our approach detects 534 ICC leaks in 108 apps from MalGenome and 2,395 ICC leaks in 337 apps in a set of 15,000 Google Play apps. [less ▲]

Similarity testing for access control

in Information and Software Technology (2015), 58

Context: Access control is among the most important security mechanisms, and XACML is the de facto standard for specifying, storing and deploying access control policies. Since it is critical that ... [more ▼]

Context: Access control is among the most important security mechanisms, and XACML is the de facto standard for specifying, storing and deploying access control policies. Since it is critical that enforced policies are correct, policy testing must be performed in an effective way to identify potential security flaws and bugs. In practice, exhaustive testing is impossible due to budget constraints. Therefore the tests need to be prioritized so that resources are focused on their most relevant subset. Objective: This paper tackles the issue of access control test prioritization. It proposes a new approach for access control test prioritization that relies on similarity. Method: The approach has been applied to several policies and the results have been compared to random prioritization (as a baseline). To assess the different prioritization criteria, we use mutation analysis and compute the mutation scores reached by each criterion. This helps assessing the rate of fault detection. Results: The empirical results indicate that our proposed approach is effective and its rate of fault detection is higher than that of random prioritization. Conclusion: We conclude that prioritization of access control test cases can be usefully based on similarity criteria. © 2014 Elsevier B.V. All rights reserved. [less ▲]

Are Your Training Datasets Yet Relevant? - An Investigation into the Importance of Timeline in Machine Learning-Based Malware Detection

in Engineering Secure Software and Systems - 7th International Symposium ESSoS 2015, Milan, Italy, March 4-6, 2015. Proceedings (2015)

In this paper, we consider the relevance of timeline in the construction of datasets, to highlight its impact on the performance of a machine learning-based malware detection scheme. Typically, we show ... [more ▼]

In this paper, we consider the relevance of timeline in the construction of datasets, to highlight its impact on the performance of a machine learning-based malware detection scheme. Typically, we show that simply picking a random set of known malware to train a malware detector, as it is done in many assessment scenarios from the literature, yields significantly biased results. In the process of assessing the extent of this impact through various experiments, we were also able to con- firm a number of intuitive assumptions about Android malware. For instance, we discuss the existence of Android malware lineages and how they could impact the performance of malware detection in the wild. [less ▲]