Scyther : semantics and verification of security protocols

Recent technologies have cleared the way for large scale application of electronic communication. The open and distributed nature of these communications implies that the communication medium is no longer completely controlled by the communicating parties. As a result, there has been an increasing demand for research in establishing secure communications over insecure networks, by means of security protocols. In this thesis, a formal model for the description and analysis of security protocols at the process level is developed. At this level, under the assumption of perfect cryptography, the analysis focusses on detecting aws and vulnerabilities of the security protocol. Starting from ??rst principles, operational semantics are developed to describe security protocols and their behaviour. The resulting model is parameterized, and can e.g. capture various intruder models, ranging from a secure network with no intruder, to the strongest intruder model known in literature. Within the security protocol model various security properties are de??ned, such as secrecy and various forms of authentication. A number of new results about these properties are formulated and proven correct. Based on the model, an automated veri??cation procedure is developed, which signi ??cantly improves over existing methods. The procedure is implemented in a prototype, which outperforms other tools. Both the theory and tool are applied in two novel case studies. Using the tool prototype, new results are established in the area of protocol composition, leading to the discovery of a class of previously undetected attacks. Furthermore, a new protocol in the area of multiparty authentication is developed. The resulting protocol is proven correct within the framework

Foundations of Security Analysis and Design III, FOSAD 2004/2005- Tutorial Lectures

he increasing relevance of security to real-life applications, such as electronic commerce and Internet banking, is attested by the fast-growing number of research groups, events, conferences, and summer schools that address the study of foundations for the analysis and the design of security aspects. This book presents thoroughly revised versions of eight tutorial lectures given by leading researchers during two International Schools on Foundations of Security Analysis and Design, FOSAD 2004/2005, held in Bertinoro, Italy, in September 2004 and September 2005. The lectures are devoted to: Justifying a Dolev-Yao Model under Active Attacks, Model-based Security Engineering with UML, Physical Security and Side-Channel Attacks, Static Analysis of Authentication, Formal Methods for Smartcard Security, Privacy-Preserving Database Systems, Intrusion Detection, Security and Trust Requirements Engineering

Model checking security protocols : a multiagent system approach

Security protocols specify the communication required to achieve security objectives, e.g., data-privacy. Such protocols are used in electronic media: e-commerce, e-banking, e-voting, etc. Formal verification is used to discover protocol-design flaws. In this thesis, we use a multiagent systems approach built on temporal-epistemic logic to model and analyse a bounded number of concurrent sessions of authentication and key-establishment protocols executing in a Dolev-Yao environment. We increase the expressiveness of classical, trace-based frameworks by mapping each protocol requirement into a hierarchy of temporal-epistemic formulae. To automate our methodology, we design and implement a tool called PD2IS. From a high-level protocol description, PD2IS produces our protocol model and the temporal-epistemic specifications of the protocol’s goals. This output is verified with the model checker MCMAS. We benchmark our methodology on various protocols drawn from standard repositories. We extend our approach to formalise protocols described by equations of cryptographic primitives. The core of this extension is an indistinguishability relation to accommodate the underlying protocol equations. Based on this relation, we introduce a knowledge modality and an algorithm to model check multiagent systems against it. These techniques are applied to verify e-voting protocols. Furthermore, we develop our methodology towards intrusion-detection techniques. We introduce the concept of detectability, i.e., the ability of protocol participants to detect jointly that the protocol is being attacked. We extend our formalisms and PD2IS to support detectability analysis. We model check several attack-prone protocols against their detectability specifications

Prosumer Nanogrids: A Cybersecurity Assessment

Nanogrids are customer deployments that can generate and inject electricity into the power grid. These deployments are based on behind-the-meter renewable energy resources and are labeled as “prosumer setups”, allowing customers to not only consume electricity, but also produce it. A residential nanogrid is comprised of a physical layer that is a household-scale electric power system, and a cyber layer that is used by manufacturers and/or grid operators to remotely monitor and control the nanogrid. With the increased penetration of renewable energy resources, nanogrids are at the forefront of a paradigm shift in the operational landscape and their correct operation is vital to the electric power grid. In this paper, we perform a cybersecurity assessment of a state-of-the art residential nanogrid deployment. For this purpose, we deployed a real-world experimental nanogrid setup that is based on photovoltaic (PV) generation. We analyzed the security and the resiliency of this system at both the cyber and physical layers. While we noticed improvements in the cybersecurity measures employed in the current nanogrid compared to previous generations, there are still major concerns. Our experiments show that these concerns range from exploiting well-known protocols, such as Secure Shell (SSH) and Domain Name Service (DNS), to the leakage of confidential information, and major shortcomings in the software updating mechanism. While the compromise of multiple nanogrids can have a negative effect on the entire power grid, we focus our analysis on individual households and have determined through Simulink-based simulations the economic loss of a compromised deployment.National Science Foundation under Grant 1850406

Model Checking Security Protocols: A Multiagent System Approach

Security protocols specify the communication required to achieve security objectives, e.g., data-privacy. Such protocols are used in electronic media: e-commerce, e-banking, e-voting, etc. Formal verification is used to discover protocol-design flaws. In this thesis, we use a multiagent systems approach built on temporal-epistemic logic to model and analyse a bounded number of concurrent sessions of authentication and key-establishment protocols executing in a Dolev-Yao environment. We increase the expressiveness of classical, trace-based frameworks by mapping each protocol requirement into a hierarchy of temporal-epistemic formulae. To automate our methodology, we design and implement a tool called PD2IS. From a high-level protocol description, PD2IS produces our protocol model and the temporal-epistemic specifications of the protocol’s goals. This output is verified with the model checker MCMAS. We benchmark our methodology on various protocols drawn from standard repositories. We extend our approach to formalise protocols described by equations of cryptographic primitives. The core of this extension is an indistinguishability relation to accommodate the underlying protocol equations. Based on this relation, we introduce a knowledge modality and an algorithm to model check multiagent systems against it. These techniques are applied to verify e-voting protocols. Furthermore, we develop our methodology towards intrusion-detection techniques. We introduce the concept of detectability, i.e., the ability of protocol participants to detect jointly that the protocol is being attacked. We extend our formalisms and PD2IS to support detectability analysis. We model check several attack-prone protocols against their detectability specifications

Conceptual Model and Architecture of MAFTIA

This deliverable builds on the work reported in [MAFTIA 2000] and [Powell and Stroud 2001]. It contains a further refinement of the MAFTIA conceptual model and a revised discussion of the MAFTIA architecture. It also introduces the work done in MAFTIA on verification and assessment of security properties, which is reported on in more detail in [Adelsbach and Creese 2003