An Approach to Select Cost-Effective Risk Countermeasures Exemplified in CORAS

Risk is unavoidable in business and risk management is needed amongst others to set up good security policies. Once the risks are evaluated, the next step is to decide how they should be treated. This involves managers making decisions on proper countermeasures to be implemented to mitigate the risks. The countermeasure expenditure, together with its ability to mitigate risks, is factors that affect the selection. While many approaches have been proposed to perform risk analysis, there has been less focus on delivering the prescriptive and specific information that managers require to select cost-effective countermeasures. This paper proposes a generic approach to integrate the cost assessment into risk analysis to aid such decision making. The approach makes use of a risk model which has been annotated with potential countermeasures, estimates for their cost and effect. A calculus is then employed to reason about this model in order to support decision in terms of decision diagrams. We exemplify the instantiation of the generic approach in the CORAS method for security risk analysis.Comment: 33 page

Decision support for choice of security solution: the Aspect-Oriented Risk Driven Development (AORDD)framework

In security assessment and management there is no single correct solution to the identified security problems or challenges. Instead there are only choices and tradeoffs. The main reason for this is that modern information systems and security critical information systems in particular must perform at the contracted or expected security level, make effective use of available resources and meet end-users' expectations. Balancing these needs while also fulfilling development, project and financial perspectives, such as budget and TTM constraints, mean that decision makers have to evaluate alternative security solutions.\ud \ud This work describes parts of an approach that supports decision makers in choosing one or a set of security solutions among alternatives. The approach is called the Aspect-Oriented Risk Driven Development (AORDD) framework, combines Aspect-Oriented Modeling (AOM) and Risk Driven Development (RDD) techniques and consists of the seven components: (1) An iterative AORDD process. (2) Security solution aspect repository. (3) Estimation repository to store experience from estimation of security risks and security solution variables involved in security solution decisions. (4) RDD annotation rules for security risk and security solution variable estimation. (5) The AORDD security solution trade-off analysis and trade-o¤ tool BBN topology. (6) Rule set for how to transfer RDD information from the annotated UML diagrams into the trad-off tool BBN topology. (7) Trust-based information aggregation schema to aggregate disparate information in the trade-o¤ tool BBN topology. This work focuses on components 5 and 7, which are the two core components in the AORDD framework

The HORM Diagramming Tool: A Domain-Specific Modelling Tool for SME Cybersecurity Awareness

Improving security posture while addressing human errors made by employees are among the most challenging tasks for SMEs concerning cybersecurity risk management. To facilitate these measures, a domain-specific modelling tool for visualising cybersecurity-related user journeys, called the HORM Diagramming Tool (HORM-DT), is introduced. By visualising SMEs’ cybersecurity practices, HORM-DT aims to raise their cybersecurity awareness by highlighting the related gaps, thereby ultimately informing new or updated cyber-risk strategies. HORM-DT’s target group consists of SMEs’ employees with various areas of technical expertise and different backgrounds. The tool was developed as part of the Human and Organisational Risk Modelling (HORM) framework, and the underlying formalism is based on the Customer Journey Modelling Language (CJML) as extended by elements of the CORAS language to cover cybersecurity-related user journeys. HORM-DT is a fork of the open-source Diagrams.net software, which was modified to facilitate the creation of cybersecurity-related diagrams. To evaluate the tool, a usability study following a within-subject design was conducted with 29 participants. HORM-DT achieved a satisfactory system usability scale score of 80.69, and no statistically significant differences were found between participants with diverse diagramming tool experience. The tool’s usability was also praised by participants, although there were negative comments regarding its functionality of connecting elements with lines.publishedVersio

A Comparison of Security Risk Analysis in the In-house IT Infrastructure and Cloud Infrastructure for the Payment Gateway System

Infrastruktuuri lahendused viiakse pilve tänu paremale juhtimisvõimekusele, seadmete tehnilisele arengule ning pilve lahenduste paindlikkusele ja kuluefektiivsetele võimalustele. Seetõttu muutub ettevõtte arhitektuur, kui süsteemid viiakse uude infrastruktuuri. Selliste muutuste tõttu võivad turvariskid suureneda või väheneda, avalduda uued riskid või suudetakse kõrvaldada mõned olemasolevad riskid. Ainult äriprotsesside modelleerimisele tugineva riskianalüüsi puhul, kus tuvastatakse ettevõtte varade väärtus, puudub IT-infrastruktuuri ja äriprotsesside omavahelise seose esindamine. Seega võib riskianalüüsis teatud infosüsteemi (IS) varasid hoopis eirata. Kahe infrastruktuuri turvariskide analüüsimisel tuleb arvestada ettevõtte arhitektuurilisi erinevusi, sest identifitseerimata IS varad võivad olla haavatavad ja kujutada ohtu käsitletavale organisatsioonile. Käesolevas töös tuvastatakse arhitektuuri modelleerimise kaudu varad, mis on vajalikud riskianalüüsi tegemiseks. Koostatud mudelid näitavad erinevusi, mis on seotud IS varadega organisatsiooni sisemise infrastruktuuri ja pilves vahel. Organisatsiooni arhitektuurist tulenevate IS varadega seotud turvariskide kindlaksmääramisel kasutatakse STRIDE taksonoomia põhist ohu modelleerimist.Selles uurimistöös esitletakse protseduuri, mis aitab organisatsioonidel tuvastada kahe infrastruktuuri IS varade muutusi ja mõista turvariskide erinevusi. Käesolevas uurimistöös kasutatud arhitektuuri modelleerimine illustreerib IS varade erinevusi ja näitab, kuidas äriprotsesse saab kaardistada tehnoloogia komponentidega. Seejärel võimaldab ohu modelleerimine struktuurselt määrata süsteemi ohtusid. Vastavad turvariskid kategoriseeritakse põhinedes uue infrastruktuuri olemasolule. Riskidega seotud muutused toovad esile ettevõtte sisemise infrastruktuuri ja pilve infrastruktuuri vahe. Selline lähenemisviis on kinnitatud ekspertide poolt. Käesolev uurimistöö põhineb juhtumiuuringul, mis käsitleb Põhja-Euroopas kasutatavat maksekanali süsteemi.In-house infrastructures are migrated to the cloud owing to the enhanced technical management capabilities, technical advancement as well as the flexibility and cost-effective options offered by the cloud. Moreover, an enterprise architecture changes when the sys-tems are moved into a different infrastructure. Due to such infrastructural changes, secu-rity risks can increase or decrease, while new risks can be introduced and some risks can be eliminated. Asset identification for risk analysis based only on business process mod-elling lacks the integration and representation of the interrelationship between IT infra-structure and business processes. Hence, certain information system (IS) assets can be neglected in the risk analysis. When analysing the security risk of two infrastructures, enterprise architectural differences need to be captured, since unidentified IS assets could be vulnerable and pose a security risk to the concerned organisation.In this thesis, assets are identified via architectural modelling to perform risk analysis. Furthermore, models present the differences pertaining to IS assets within in-house infra-structure and cloud infrastructure, in addition to the mapping to corresponding business processes. The STRIDE-based threat modelling is employed to determine the security risks concerning IS assets derived from enterprise architecture.To elaborate, this study will introduce a procedure that will help organisations identify IS asset changes of two different infrastructures and capture security risk changes. Moreover, architectural modelling applied in this research will illustrate the differences regard-ing IS assets and present the way in which business processes are mapped to technology components. Subsequently, a threat modelling method employed will provide a structural way to identify threats to the systems. The changes incorporated concerning the security risks will further present the security risk gap regarding in-house infrastructure and cloud infrastructure. Additionally, the validation of this approach is performed by domain experts. The enterprise architecture modelled in this thesis is based on a case study dealing with a payment gateway system used in North Europe

A business-oriented framework for enhancing web services security for e-business

Security within the Web services technology field is a complex and very topical issue. When considering using this technology suite to support interacting e-businesses, literature has shown that the challenge of achieving security becomes even more elusive. This is particularly true with regard to attaining a level of security beyond just applying technologies, that is trusted, endorsed and practiced by all parties involved. Attempting to address these problems, this research proposes BOF4WSS, a Business-Oriented Framework for enhancing Web Services Security in e-business. The novelty and importance of BOF4WSS is its emphasis on a tool-supported development methodology, in which collaborating e-businesses could achieve an enhanced and more comprehensive security and trust solution for their services interactions. This investigation began with an in-depth assessment of the literature in Web services, e-business, and their security. The outstanding issues identified paved the way for the creation of BOF4WSS. With appreciation of research limitations and the added value of framework tool-support, emphasis was then shifted to the provision of a novel solution model and tool to aid companies in the use and application of BOF4WSS. This support was targeted at significantly easing the difficulties incurred by businesses in transitioning between two crucial framework phases. To evaluate BOF4WSS and its supporting model and tool, a two-step approach was adopted. First, the solution model and tool were tested for compatibility with existing security approaches which they would need to work with in real-world scenarios. Second, the framework and tool were evaluated using interviews with industry-based security professionals who are experts in this field. The results of both these evaluations indicated a noteworthy degree of evidence to affirm the suitability and strength of the framework, model and tool. Additionally, these results also act to cement this thesis' proposals as innovative and significant contributions to the research field

Architecture-based Qualitative Risk Analysis for Availability of IT Infrastructures

An IT risk assessment must deliver the best possible quality of results in a time-effective way. Organisations are used to customise the general-purpose standard risk assessment methods in a way that can satisfy their requirements. In this paper we present the QualTD Model and method, which is meant to be employed together with standard risk assessment methods for the qualitative assessment of availability risks of IT architectures, or parts of them. The QualTD Model is based on our previous quantitative model, but geared to industrial practice since it does not require quantitative data which is often too costly to acquire. We validate the model and method in a real-world case by performing a risk assessment on the authentication and authorisation system of a large multinational company and by evaluating the results w.r.t. the goals of the stakeholders of the system. We also perform a review of the most popular standard risk assessment methods and an analysis of which one can be actually integrated with our QualTD Model

Exiting the risk assessment maze: A meta-survey

Organizations are exposed to threats that increase the risk factor of their ICT systems. The assurance of their protection is crucial, as their reliance on information technology is a continuing challenge for both security experts and chief executives. As risk assessment could be a necessary process in an organization, one of its deliverables could be utilized in addressing threats and thus facilitate the development of a security strategy. Given the large number of heterogeneous methods and risk assessment tools that exist, comparison criteria can provide better understanding of their options and characteristics and facilitate the selection of a method that best fits an organization’s needs. This paper aims to address the problem of selecting an appropriate risk assessment method to assess and manage information security risks, by proposing a set of comparison criteria, grouped into 4 categories. Based upon them, it provides a comparison of the 10 popular risk assessment methods that could be utilized by organizations to determine the method that is more suitable for their needs. Finally, a case study is presented to demonstrate the selection of a method based on the proposed criteri

Modeling Security Risks at the System Design Stage Alignment of Mal Activity Diagrams and SecureUML to the ISSRM Domain Model

Turvatehnika disain on üks olulisi süsteemiarenduse komponente. Ta peaks läbima tervet süsteemiarendusprotsessi. Kahjuks pööratakse talle paljudel juhtudel tähelepanu ainult süsteemi arendamise ja haldamise ajal. Paljud turvalise modelleerimise keeled (näiteks Misuse Case, Secure Tropos) aitavad turvariskejuba nõuete analüüsi etapil hallata. Käesolevas magistritöös vaatleme modelleerimisvahendeid (pahateoskeemid ja SecureUML), mida kasutatakse süsteemi disainil. Täpsemalt, me uurime, kuivõrd need vahendid toetavad infosüsteemide turvariskide haldust (Information Systems Security Risks Management, ISSRM). Töö tulemuseks on tabel, mis seab pahateoskeemid ning SecureUML-keele konstruktsioonid ISSRM domeeni mõistetega omavahel vastavusse. Me põhjendame oma analüüsi ning valideerime saadud tulemusi mitmel illustratiivsel näitel. Me loodame, et saadud tulemused aitavad arendajatel paremini aru saada, kuidas turvariske süsteemi disainietapil arvesse võtta. Peale selle, nende keelte analüüs ühisel kontseptuaalsel taustal annab tulevikus võimaluse neid keeli korraga kasutada ning loodud mudeleid ühest keelest teise teisendada.Security engineering is one of the important concerns during system development. It should be addressed throughout the whole system development process; however in many cases it is often dealt only during system development and maintenance. There are several security modeling languages (e.g, Misuse case, Secure Tropos) that help dealing with security risk management at the requirements stage. In this thesis, we are focusing on the modeling languages (e.g. Mal activity diagrams and SecureUML) that are used to design the system. More specifically we investigate how these languages support information systems security risks management (ISSRM). The outcome of this work is an alignment table between the Mal activity diagrams and SecureUML language constructs to the ISSRM domain model concepts. We ground our analysis and validate the received results on the number of illustrative examples. We hope that our results will help developers to understand how they can consider security risks at the system design stage. In addition we open the way for the interoperability between different modeling languages that are analysed using the same conceptual background, thus, potentially leading to the transformation between these modeling approaches