Security of Contactless Smart Card Protocols

Tato práce analyzuje hrozby pro protokoly využívající bezkontaktní čipové karty a představuje metodu pro poloautomatické hledání zranitelností v takových protokolech pomocí model checkingu. Návrh a implementace bezpečných aplikací jsou obtížné úkoly, i když je použit bezpečný hardware. Specifikace na vysoké úrovni abstrakce může vést k různým implementacím. Je důležité používat čipovou kartu správně, nevhodná implementace protokolu může přinést zranitelnosti, i když je protokol sám o sobě bezpečný. Cílem této práce je poskytnout metodu, která může být využita vývojáři protokolů k vytvoření modelu libovolné čipové karty, se zaměřením na bezkontaktní čipové karty, k vytvoření modelu protokolu a k použití model checkingu pro nalezení útoků v tomto modelu. Útok může být následně proveden a pokud není úspěšný, model je upraven pro další běh model checkingu. Pro formální verifikaci byla použita platforma AVANTSSAR, modely jsou psány v jazyce ASLan++. Jsou poskytnuty příklady pro demonstraci použitelnosti navrhované metody. Tato metoda byla použita k nalezení slabiny bezkontaktní čipové karty Mifare DESFire. Tato práce se dále zabývá hrozbami, které není možné pokrýt navrhovanou metodou, jako jsou útoky relay. This thesis analyses contactless smart card protocol threats and presents a method of semi-automated vulnerability finding in such protocols using model checking. Designing and implementing secure applications is difficult even when secure hardware is used. High level application specifications may lead to different implementations. It is important to use the smart card correctly, inappropriate protocol implementation may introduce a vulnerability, even if the protocol is secure by itself. The goal of this thesis is to provide a method that can be used by protocol developers to create a model of arbitrary smart card, with focus on contactless smart cards, to create a model of the protocol, and to use model checking to find attacks in this model. The attack can be then executed and if not successful, the model is refined for another model checker run. The AVANTSSAR platform was used for the formal verification, models are written in the ASLan++ language. Examples are provided to demonstrate usability of the proposed method. This method was used to find a weakness of Mifare DESFire contactless smart card. This thesis also deals with threats not possible to cover by the proposed method, such as relay attacks.

Design, Formal Specification and Analysis of Multi-Factor Authentication Solutions with a Single Sign-On Experience

Over the last few years, there has been an almost exponential increase of the number of mobile applications that deal with sensitive data, such as applications for e-commerce or health. When dealing with sensitive data, classical authentication solutions based on username-password pairs are not enough, and multi-factor authentication solutions that combine two or more authentication elements of different categories are required. Many different such solutions are available, but they usually cover the scenario of a user accessing web applications on their laptops, whereas in this paper we focus on native mobile applications. This changes the exploitable attack surface and thus requires a specific analysis. In this paper, we present the design, the formal specification and the security analysis of a solution that allows users to access different mobile applications through a multi-factor authentication solution providing a Single Sign-On experience. The formal and automated analysis that we performed validates the security goals of the solution we propose

Principles of Security and Trust: 7th International Conference, POST 2018, Held as Part of the European Joint Conferences on Theory and Practice of Software, ETAPS 2018, Thessaloniki, Greece, April 14-20, 2018, Proceedings

authentication; computer science; computer software selection and evaluation; cryptography; data privacy; formal logic; formal methods; formal specification; internet; privacy; program compilers; programming languages; security analysis; security systems; semantics; separation logic; software engineering; specifications; verification; world wide we

Formal Analysis and Verification of OAuth 2.0 in SSO

This thesis examines the OAuth 2.0 protocol within Single Sign-On (SSO) systems through modelling and formal analysis. The versatile Performing Security Proofs of Stateful Protocols (PSPSP), a theory for the Isabelle/HOL proof assistant was used to carry out the verification. Additionally the Open-Source Fixedpoint Model-Checker (OFMC), was used in this verification for its accessibility. PSPSP notably supports the modelling of mutable long-term state, a feature not common in many similar tools. The challenge lies in crafting a model that accurately mirrors real-world scenarios while integrating the OAuth 2.0 protocol on top of the TLS 1.2 protocol. The goal is to produce a model that is both realistic and doesn't induce false attack vectors in its abstraction. The complexity of combining SSO, OAuth, and TLS often necessitates simplifications for effective verification. This study explores the modelling of OAuth components without drastic over-simplifications, verifying each in isolation, and then applying compositional reasoning available in PSPSP/Isabelle to introduce the TLS protocol as well. This process necessitates a well-defined interface between components and verification of all components individually and in the composition. Both tools confirm the lack of detectable vulnerabilities in the OAuth 2.0 protocol, reinforcing its security and prominence in SSO systems. The research explores the process of modelling and formally verifying security protocols, and deepens the understanding of OAuth 2.0's role in SSO systems

Securing Personal IoT Platforms through Systematic Analysis and Design

Our homes, hospitals, cities, and industries are being enhanced with devices that have computational and networking capabilities. This emerging network of connected devices, or Internet of Things (IoT), promises better safety, enhanced management of patients, improved energy efficiency, and optimized manufacturing processes. Although there are many such benefits, security vulnerabilities in these systems can lead to user dissatisfaction (e.g., from random bugs), privacy violation (e.g., from stolen information), monetary loss (e.g., denial-of-service attacks or ``ransomware''), or even loss of life (e.g., from malicious actors manipulating critical processes in a hospital). Security design flaws may manifest at several layers of the IoT software/hardware stack. This work focuses on design flaws that arise in IoT platforms---software systems that manage devices, data analysis results and control logic. Specifically, we show that empirical security-oriented analyses of personal IoT platforms lead to: (1) an understanding of design flaws that can be leveraged in long-range and device-independent attacks; (2) the development of security mechanisms that limit the potential for these attacks. Concretely, we contribute empirical analyses for two categories of personal IoT platforms---Hub-Based (Samsung SmartThings), and Cloud-First (If-This-Then-That). Our analyses reveal overprivilege as a main enabler for attacks, and we propose a set of information flow control techniques (FlowFence and Decoupled-IFTTT) to manage privilege better in these platforms, therefore reducing the potential for attacks.PHDComputer Science & EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/137083/1/earlence_1.pd

Automated Security Analysis of Web Application Technologies

TheWeb today is a complex universe of pages and applications teeming with interactive content that we use for commercial and social purposes. Accordingly, the security of Web applications has become a concern of utmost importance. Devising automated methods to help developers to spot security flaws and thereby make the Web safer is a challenging but vital area of research. In this thesis, we leverage static analysis methods to automatically discover vulnerabilities in programs written in JavaScript or PHP. While JavaScript is the number one language fueling the client-side logic of virtually every Web application, PHP is the most widespread language on the server side. In the first part, we use a series of program transformations and information flow analysis to examine the JavaScript Helios voting client. Helios is a stateof- the-art voting system that has been exhaustively analyzed by the security community on a conceptual level and whose implementation is claimed to be highly secure. We expose two severe and so far undiscovered vulnerabilities. In the second part, we present a framework allowing developers to analyze PHP code for vulnerabilities that can be freely modeled. To do so, we build socalled code property graphs for PHP and import them into a graph database. Vulnerabilities can then be modeled as appropriate database queries. We show how to model common vulnerabilities and evaluate our framework in a large-scale study, spotting hundreds of vulnerabilities.DasWeb hat sich zu einem komplexen Netz aus hochinteraktiven Seiten und Anwendungen entwickelt, welches wir täglich zu kommerziellen und sozialen Zwecken einsetzen. Dementsprechend ist die Sicherheit von Webanwendungen von höchster Relevanz. Das automatisierte Auffinden von Sicherheitslücken ist ein anspruchsvolles, aber wichtiges Forschungsgebiet mit dem Ziel, Entwickler zu unterstützen und das Web sicherer zu machen. In dieser Arbeit nutzen wir statische Analysemethoden, um automatisiert Lücken in JavaScript- und PHP-Programmen zu entdecken. JavaScript ist clientseitig die wichtigste Sprache des Webs, während PHP auf der Serverseite am weitesten verbreitet ist. Im ersten Teil nutzen wir eine Reihe von Programmtransformationen und Informationsflussanalyse, um den JavaScript HeliosWahl-Client zu untersuchen. Helios ist ein modernesWahlsystem, welches auf konzeptueller Ebene eingehend analysiert wurde und dessen Implementierung als sehr sicher gilt. Wir enthüllen zwei schwere und bis dato unentdeckte Sicherheitslücken. Im zweiten Teil präsentieren wir ein Framework, das es Entwicklern ermöglicht, PHP Code auf frei modellierbare Schwachstellen zu untersuchen. Zu diesem Zweck konstruieren wir sogenannte Code-Property-Graphen und importieren diese anschließend in eine Graphdatenbank. Schwachstellen können nun als geeignete Datenbankanfragen formuliert werden. Wir zeigen, wie wir herkömmliche Schwachstellen modellieren können und evaluieren unser Framework in einer groß angelegten Studie, in der wir hunderte Sicherheitslücken identifizieren.CISP