Matus Korman

A Bayesian network model for likelihood estimations of acquirement of critical software vulnerabilities and exploits

Context: Software vulnerabilities in general, and software vulnerabilities with publicly available exploits in particular, are important to manage for both developers and users. This is however a d ...

A Requirements Based Approach for Automating Enterprise IT Architecture Modeling Using Multiple Data Sources

Enterprise Architecture (EA) is an approach where models of an enterprise are used for decision support. An important part of EA is enterprise IT architecture. Creating models of both types can be a complex task. EA can be difficult to model due to unavailable business data, while in the case of enterprise IT architecture, there can be too much IT data available. Furthermore, there is a trend of a growing availability of data possibly useful for modeling. We call the process of making use of available data, automatic modeling. There have been previous attempts to achieve automatic model creation using a single source of data. Often, a single source of data is not enough to create the models required. In this paper we address automatic modeling when data from multiple heterogeneous sources are needed. The paper looks at the potential data sources, requirements that the data must meet and proposes a four-part approach. The approach is tested in a study using the Cyber Security Modeling Language in order to model a lab setup at KTH Royal Institute of Technology. The lab aims at mirroring a small power utilitys IT setup. The paper demonstrates that it is possible to create timely and scalable enterprise IT architecture models from multiple sources, and that manual modeling and data quality related problems can be resolved using known data processing methods.

Technology management through architecture reference models: A smart metering case

Enterprise architecture (EA) has become an essential part of managing technology in large enterprises. These days, automated analysis of EA is gaining increased attention. That is, using models of business and technology combined in order to analyze aspects such as cyber security, complexity, cost, performance, and availability. However, gathering all Information needed and creating models for such analysis is a demanding and costly task. To lower the efforts needed a number of approaches have been proposed, the most common are automatic data collection and reference models. However these approaches are all still very immature and not efficient enough for the discipline, especially when it comes to using the models for analysis and not only for documentation and communication purposes. In this paper we propose a format for representing reference models focusing on analysis. The format is tested with a case in a large European project focusing on security in advanced metering infrastructure. Thus we have, based on the format, created a reference model for smart metering architecture and cyber security analysis. On a theoretical level we discuss the potential impact such a reference model can have.

Modeling Enterprise Authorization: A Unified Metamodel and Initial Validation

Authorization and its enforcement, access control, have stood at the beginning of the art and science of information security, and remain being crucial pillar of security in the information technology (IT) and enterprises operations. Dozens of different models of access control have been proposed. Although Enterprise Architecture as the discipline strives to support the management of IT, support for modeling access policies in enterprises is often lacking, both in terms of supporting the variety of individual models of access control nowadays used, and in terms of providing a unified ontology capable of flexibly expressing access policies for all or the most of the models. This study summarizes a number of existing models of access control, proposes a unified metamodel mapped to ArchiMate, and illustrates its use on a selection of example scenarios and two business cases.

Analyzing attack resilience of an advanced meter infrastructure reference model

Advanced metering infrastructure (AMI) is a key component of the concept of smart power grids. Although several functional/logical reference models of AMI exist, they are not suited for automated analysis of properties such as cyber security. This paper briefly presents a reference model of AMI that follows a tested and even commercially adopted formalism allowing automated analysis of cyber security. Finally, this paper presents an example cyber security analysis, and discusses its results.

Analyzing the Effectiveness of Attack Countermeasures in a SCADA System

The SCADA infrastructure is a key component for power grid operations. Securing the SCADA infrastructure against cyber intrusions is thus vital for a well-functioning power grid. However, the task remains a particular challenge, not the least since not all available security mechanisms are easily deployable in these reliability-critical and complex, multi-vendor environments that host modern systems alongside legacy ones, to support a range of sensitive power grid operations. This paper examines how effective a few countermeasures are likely to be in SCADA environments, including those that are commonly considered out of bounds. The results show that granular network segmentation is a particularly effective countermeasure, followed by frequent patching of systems (which is unfortunately still difficult to date). The results also show that the enforcement of a password policy and restrictive network configuration including whitelisting of devices contributes to increased security, though best in combination with granular network segmentation.

Integrated Multi-Domain Risk Assessment Using Automated Hypothesis Testing

In this paper we present an approach for the integration of cybersecurity tools from multiple domains into an overall risk assessment framework which takes the complex interactions between domains in smart grid systems into account. The approach is based on generating hypotheses from a template, which are then analyzed for their probability and associated impact on the system. The feasibility of the proposed approach is discussed using a very simple example case to serve as a proof of concept. Furthermore, we introduce a generic software framework for the processing of hypothesis templates.

Automated architecture modeling for enterprise technology manageme using principles from data fusion: A security analysis case

Architecture models are used in enterprise management for decision support. These decisions range from designing processes to planning for the appropriate supporting technology. It is unreasonable for an existing enterprise to completely reinvent itself. Incremental changes are in most cases a more resource efficient tactic. Thus, for planning organizational changes, models of the current practices and systems need to be created. For mid-sized to large organizations this can be an enormous task when executed manually. Fortunately, theres a lot of data available from different sources within an enterprise that can be used for populating such models. The data are however almost always heterogeneous and usually only representing fragmented views of certain aspects. In order to merge such data and obtaining a unified view of the enterprise a suitable methodology is needed. In this paper we address this problem of creating enterprise architecture models from heterogeneous data. The paper proposes a novel approach that combines methods from the fields of data fusion and data warehousing. The approach is tested using a modeling language focusing on cyber security analysis in a study of a lab setup mirroring a small power utilitys IT environment.

Integrated Metamodel for Security Analysis

This paper proposes a metamodel for analyzing security aspects of enterprise architecture by combining analysis of cybersecurity with analysis of interoperability and availability. The metamodel extends an existing attack graph based metamodel for cyber security modeling and evaluation, P2CySeMoL, and incorporates several new elements and evaluation rules. The approach improves security analysis by combining two ways of evaluating reach ability: one which considers ordinary user activity and another, which considers technically advanced techniques for penetration and attack. It is thus permitting to evaluate security in interoperability terms by revealing attack possibilities of legitimate users. Combined with data import from various sources, like an enterprise architecture data repository, the instantiations of the proposed metamodel allow for a more holistic overview of the threats to the architecture than the previous version. Additional granularity is added to the analysis with the reach ability need concept and by enabling the consideration of unavailable and unreliable systems.

A Study on Software Vulnerabilities and Weaknesses of Embedded Systems in Power Networks

In this paper we conduct an empirical study with the purpose of identifying common software weaknesses of embedded devices used as part of industrial control systems in power grids. The data is gathered about the devices and software of 6 companies, ABB, General Electric, Schneider Electric, Schweitzer Engineering Laboratories, Siemens and Wind River. The study uses data from the manufacturersfi online databases, NVD, CWE and ICS CERT. We identified that the most common problems that were reported are related to the improper input validation, cryptographic issues, and programming errors.