
The safety and security of critical infrastructures is both a technical and a social issue. However, most risk analysis methods focus predominantly on technical aspects and ignore the impact strategic human decisions have on the behavior of systems. Furthermore, the high degree of complexity and lack of historical data for probability estimations in case of new and emerging systems seriously limit the practical utility of traditional risk analysis methods. The Conflicting Incentives Risk Analysis (CIRA) method concentrates on human decision-makers to address these problems. However, the method’s applicability is restricted by the fact that humans are not represented in the Smart Grid Architecture Model (SGAM) which is the industry’s most well-known model of the Smart Grid ecosystem. Therefore, the main objective of this paper is to establish a connection between CIRA and SGAM by proposing the SGAM-H, an enhanced version of the original architecture model complemented by the Human Layer. The development and evaluation of the artifact is guided by the Design Science Research methodology. The evaluation presents a working example of applying the CIRA method on a scenario involving intra-organizational risks at a Distribution System Operator. The key benefit of the SGAM-H is that it enables the construction of a common understanding among stakeholders about risks related to key decision-makers, which is a fundamental first step towards forming a more complete picture about potential issues affecting the electric grids of the future.
This position paper connects the areas and communities of abstract argumentation and attack-defence trees in the area of security. Both areas deal with attacks, defence and support and both areas rely on applications dealing with human aggressive activities. The unifying idea we use in this paper is to regard arguments as AND-OR attack trees as proposed by Schneier in the security domain. The core model, which is acceptable for both communities, is a pair (𝐒,↠ ) , where S is a set of attack trees (the “arguments”) and ↠ is a binary relation on attack trees (the “attack” relation). This leads us to the notion of an attack-defence framework, which provides an argumentation-based semantics for attack-defence trees and more general attack-defence graphs.
In the context of insiders, preventive security measures have a high likelihood of failing because insiders ought to have sufficient privileges to perform their jobs. Instead, in this paper, we propose to treat the insider threat by a detective measure that holds an insider accountable in case of violations. However, to enable accountability, we need to create causal models that support reasoning about the causality of a violation. Current security models (e.g., attack trees) do not allow that. Still, they are a useful source for creating causal models. In this paper, we discuss the value added by causal models in the security context. Then, we capture the interaction between attack trees and causal models by proposing an automated approach to extract the latter from the former. Our approach considers insider-specific attack classes such as collusion attacks and causal-model-specific properties like preemption relations. We present an evaluation of the resulting causal models’ validity and effectiveness, in addition to the efficiency of the extraction process.
Understanding an Android malware is a difficult task that requires strong skills in reverse engineering. Few tools exist except the well know IDA and Ghidra tools that are more focused on the analysis of binaries. In the Android world, understanding a malware requires to analyze the bytecode of the application, possibly obfuscated or hidden in a benign application that has been modified. At execution time, the malware can download new payloads, compromise the smartphone, and install new apps. We believe that a security analyst would appreciate to visualize and replay an execution of an Android malware. In particular, an analysis that bridges the gap between the bytecode and the events occurring during the execution would help to understand the malware behavior. In this article, we propose GroDDViewer the first tool offering a dual view of the execution of an Android malware. The first view represents the execution at operating system level through the representation of all information flow between files, processes and sockets. The second view represents what happened in the code of the application, during its execution. The benefit of this visualization tool is illustrated on a ransomware sample. In future, we plan to evaluate the tool with a panel of users on a benchmark of malware samples.
We give diagrammatic tools to reason about information flow within encrypted communication. In particular, we are interested in deducing where information flow (communication or otherwise) has taken place, and fully accounting for all possible paths. The core mathematical concept is using a single categorical diagram to model the underlying mathematics, the epistemic knowledge of the participants, and (implicitly) the potential or actual communication between participants. A key part of this is a ‘correctness’ or ‘consistency’ criterion that ensures we accurately fully account for the distinct routes by which information may come to be known (i.e. communication and / or calculation). We demonstrate how this formalism may be applied to answer questions about communication scenarios where we have the partial information about the participants and their interactions. Similarly, we show how to analyse the consequences of changes to protocols or communications, and to enumerate the distinct orders in which events may have occurred. We use various forms of Diffie-Hellman key exchange as an illustration of these techniques. However, they are entirely general; an extended version of this paper [8] provides similar analyses of other protocols.