List of running and completed projects of our group


Cryptographic Foundations of Privacy in Distributed Ledgers

2020 – 2027 •  Vienna Science and Technology Fund (WWTF)  •  PI Georg Fuchsbauer

We are observing a trend towards decentralization, reflected in technologies such as blockchains and distributed ledgers. These enable currencies without banks, community-based platforms without commercial actors, and many more. Central to all such systems is their transparency, allowing anyone to verify the system state, which makes trust in central parties obsolete. However, transparency conflicts with protection of user privacy (meanwhile even legally enforced by GDPR) and current systems cause huge environmental damage.

The goal of COnFIDE is to use cryptography to reconcile public verifiability with privacy in distributed ledgers, and to improve efficiency and sustainability of decentralized systems, avoiding wasting energy (as for mining Bitcoins) and storage (as for massive duplication of obsolete transaction data).


Semantic and Cryptographic Foundations of Security and Privacy by Compositional Design

2023 – 2026 •  Austrian Science Fund (FWF)  •  PI Laura Kovacs  •  PI Matteo Maffei

  • Institute of Technology Austria (IST), Klosterneuburg, Austria
  • TU Graz, Graz, Austria
  • Universität Klagenfurt, Klagenfurt, Austria
  • Universität Wien, Wien


Blockchain Technologies for the Internet of Things

2020 – 2025 •  Christian Doppler Research Association (CDG)  •  PI Matteo Maffei

In recent years, Distributed Ledger Technologies (DLTs) like blockchains have gained much popularity both within industry and research. Today, DLTs are not only perceived as the underlying technology for cryptocurrencies like Bitcoin, but have also been identified as a potential disruptive technology in many different fields, e.g., supply chain tracking and healthcare. In a lot of these fields, blockchains are combined with Internet of Things (|oT) technologies in order to store data from real-world objects in a tamper-proof way, to process this data, and to share the results.

The widespread attention for DLTs has led to manifold research and development activities. These focus either on the application of blockchains in novel use cases, theenhancement of already existing technologies, or the development of completely new DLTs. As a result, today's DLT landscape is heavily fragmented, with different, incompatible technologies being available to potential users. Since interoperability between different blockchains is usually not foreseen in existing protocols and standards, functionalities like sending tokens from one participant to another, invoking and executing smart contracts, or guaranteeing validity of data stored in a blockchain can only be carried out within a single blockchain. This incompatibility contradicts the open nature of |oT- based systems, where heterogeneous technologies interact with each other, and therefore prevents the uptake of blockchains by the industry.

Therefore, the Christian Doppler Laboratory for Blockchain Technologies for the Internet of Things (CDL-BOT) will contribute to the foundations of blockchain interoperability by providing fundamental research results in the areas of cross-blockchain token transfers, cross-blockchain smart contract invocation and interaction, the integration of blockchains with further DLTs and other systems, and by providing client-side blockchain interoperability through developer support. In addition, research in the area of lightweight DLTs for the loT is conducted. While the focus of CDL-BOT is on the application of blockchain technologies in the |oT, other DLTs are also regarded. Furthermore, the research results from the laboratory are not only applicable to the |oT field, but also important for non-|oT-based systems where interoperability between different DLTs is necessary. By doing so, CDL-BOT stimulates a paradigm shift from todays closed blockchains to an open system where devices and users can interact with each other across the boundaries of DLTs.

  • IOTA Foundation, Berlin, Germany
  • Pantos GmbH, Wien, Austria


A Composable Rational Framework for Blockchain Systems

2022 – 2025 •  Austrian Science Fund (FWF)  •  PI Georgia Avarikioti

Bitcoin marked the beginning of a new era in digital finance; the data structure known as the blockchain enabled financial transactions to be executed in a secure decentralized manner, therefore revolutionizing the financial landscape. Blockchains naturally form environments where the participants act for profit (i.e., participants are rational). Nevertheless, current works typically analyze the security of blockchain protocols in the traditional setting where some of the participants are malicious and the rest are honest as there is no general framework to analyze blockchains from a rational perspective. Furthermore, blockchain systems are complex and consist of several components that handle different performance aspects, such as the network layer or Layer 0, the consensus layer or Layer 1, and the off-chain network or Layer 2. All these layers interact with each other and the security of each layer depends on the security of its substrate layer and vice versa. Therefore, the composition of protocols in the blockchain setting is vital for the security guarantees and the correct operation of cryptocurrencies. The goal of this project is to introduce a composable framework for the security analysis of blockchain protocols under a hybrid model of both rational and malicious participants. This is a significant yet currently missing tool with impact across multiple disciplines such as computer science and economics.


Foundations and Tools for Client-Side Web Security

2018 – 2024 •  European Research Council (ERC)  •  PI Matteo Maffei

The constantly increasing number of attacks on web applications shows how their rapid development has not been accompanied by adequate security foundations and demonstrates the lack of solid security enforcement tools. Indeed, web applications expose a gigantic attack surface, which hinders a rigorous understanding and enforcement of security properties. Hence, despite the worthwhile efforts to design secure web applications, users for a while will be confronted with vulnerable, or maliciously crafted, code. Unfortunately, end users have no way at present to reliably protect themselves from malicious applications. BROWSEC will develop a holistic approach to client-side web security, laying its theoretical foundations and developing innovative security enforcement technologies. In particular, BROWSEC will deliver the first client-side tool to secure web applications that is practical, in that it is implemented as an efficient and easily deployable browser extension, and also provably sound, i.e., backed up by machine-checked proofs that the tool provides end users with the required security guarantees. At the core of the proposal lies a novel monitoring technique, which treats the browser as a blackbox and intercepts its inputs and outputs in order to prevent dangerous information flows. With this lightweight monitoring approach, we aim at enforcing strong security properties without requiring any expensive and, given the dynamic nature of web applications, statically infeasible program analysis.

BROWSEC is thus a multidisciplinary research effort, promising practical impact and delivering breakthrough advancements in various disciplines, such as web security, JavaScript semantics, software engineering, and program verification.

  • Wolfgang Pauli Institute, Wien, Austria


IoTIO: Analyzing and Understanding the Internet of Insecure Things

2020 – 2024 •  Vienna Science and Technology Fund (WWTF)  •  PI Martina Lindorfer

Consumer devices, from door locks to light bulbs, are becoming increasingly smart. They are linked with other devices as part of smart homes and offices, usually Internet-connected, and may be publicly accessible through misconfiguration or IPv6.

The corresponding security and privacy implications have yet to be explored in depth, and their analysis is complicated by device type and architecture diversity. Prior work focused on case studies of specific device types, or analyzed devices' firmware in isolation, requiring substantial manual effort. In contrast, the automatic analysis of devices' interaction with their environment and other devices could uncover new vulnerability types and privacy violations.

In this project, we will propose scalable techniques to analyze smart devices for potential vulnerabilities based on how they are collecting, processing, and sharing data by interacting with their mobile companion app or smart hubs. We will provide a proof-of-concept tool to show our research's practicality.

The basis of our project are novel software and network analyses of companion apps and hub integration to synthesize protocols, discover commands to exercise device functionality, and identify information flows ‒ without requiring access to the smart devices themselves.

The project is a multi-disciplinary research effort enabling security and privacy analyses. It has also societal impact by enabling informed decision making by manufactures, lawmakers, and users.

  • Ruhr-Universität Bochum, Bochum, Germany


Cryptographic Foundations for Future-proof Internet Security

2019 – 2023 •  Austrian Science Fund (FWF)  •  PI Matteo Maffei

Today, much of our personal freedom and the power to guarantee and maintain a free society depends on cryptographic primitives (e.g., digital signatures and encryption) incorporated in the security protocols of today's Internet used for securing many daily tasks such as messaging, online banking or sending e-mails. While anticipated regulations like the upcoming EU General Data Protection Regulation (GDPR) promote the usage of cryptography to protect sensitive data, revelations about activities of governmental agencies have revealed worryingly information. Examples include subverting cryptographic software products, subverting certification authorities, backdooring cryptographic schemes, or influencing and weakening cryptographic standardization processes. Besides providing governmental institutions means to spy on citizens, such practices are highly vulnerable to also be exploited by non-governmental attackers.

Many of the public-key cryptographic schemes used to secure today's Internet were not designed with the functionality and the security requirements in mind that come along with tomorrow's envisioned use-cases on the Internet. This requires novel and typically more advanced cryptographic schemes that consider aspects that were not known or of interest in the early days of the Internet. Cryptography for a future-proof Internet needs to consider a potentially huge number of devices to which data is communicated simultaneously and shared selectively and needs to be flexible enough to work on both ends of the spectrum, i.e., resource constrained IoT devices as well as cloud-powered services. What is more, new security aspects such as readiness for a post-quantum era as well as the increasing importance of cryptographic schemes which are resilient against threats due to subversion as well as surveillance (as mentioned before) are of high relevance.

PROFET targets at designing public-key cryptography capable to secure tomorrow's Internet which will encompass paradigms such as cloud computing, the IoT and distributed ledgers as essential ingredients. We thereby want to specifically put our focus on two highly important issues for the future: (1) designing security models and cryptographic schemes that are surveillance and subversion resilient by design, e.g., provide strong notions such as forward security and post-compromise security, and (2) designing cryptographic schemes that remain secure in the presence of powerful quantum computers, i.e., schemes that provide post-quantum security. We will on the one hand work on foundational aspects, but also investigate the application of our techniques to certain problems encountered in the IoT and cloud application scenarios.


Security and Privacy Foundations of Blockchain Technologies

2020 – 2023 •  SBA Research gemeinnützige GmbH  •  PI Matteo Maffei

Blockchains are emerging as a disruptive technology for securing transactions and computations across mutually distrustful peers. The security and privacy of blockchains, however, depends on a complicated combination of cryptography, programming languages, game theory, distributed systems, and network concepts, which is not well understood. The goal of this project is to lay sound foundations for blockchain technologies, devising techniques for their provable analysis and design.


Distributed Ledger Development and Implementation

2022 – 2023 •  ABC Research GmbH  •  PI Matteo Maffei


Vienna Cybersecurity and Privacy Research Center

2019 – 2023 •  Vienna Business Agency (WAW)  •  PI Matteo Maffei

The aim of ViSP is to break down the silos and boost the existing research synergies among the partner institutions, to establish a graduate educational program in cybersecurity and privacy, and to create all together an internationally leading research and educational brand for cybersecurity and privacy in Vienna.

While the primary goals are research excellence and education, ViSP will have a significant impact on industry and regional development. Cybersecurity and privacy expertise is extremely required by enterprises, which open branches and labs in close proximity to research centers and universities leading in this field, due to the availability of the required know-how, possibilities of technology transfer, and access to specialized students. Cybersecurity and privacy are also a flourishing field worldwide for startups created by students during or at the end of their studies, which will be promoted and mentored in the incubation phase by ViSP.

The ultimate goal is to establish Vienna as the place to be for cybersecurity and privacy research in Europe. Besides the central location and the excellent quality of life, the unique selling point of the Viennese landscape in the cybersecurity and privacy domain is the unmatchable concentration of research excellence (as witnessed, e.g., by the 6 ERC grants in this field, all joining ViSP, which has no equal in Europe) and the number of universities and research centers active in this field, which however requires a consolidation effort to emerge internationally as a leading location.

  • Ruhr-Universität Bochum, Bochum, Germany


Privacy-Preserving Regulatory Technologies for Distributed Ledger Technologies

2018 – 2021 •  Austrian Research Promotion Agency (FFG)  •  PI Matteo Maffei

The rise of cryptocurrencies and their underlying distributed ledger technologies (DLT), commonly referred to as blockchains, has captured the interest of diverse communities, science and market alike. Decentralized cryptocurrencies, such as Bitcoin, are increasingly perceived as viable alternatives to classical payment methods. In March 2017, the monetary value of a "bitcoin" surpassed the value of an ounce of gold for the first time 1. Different countries all over the world are currently experimenting with incorporating cryptocurrencies into their regulatory framework. The classification and regulatory requirements when engaging with Bitcoin still varies by country or territory 2. In May 2016, the muncipality of Zug (Switzerland) started to accept Bitcoin payments for government services 3. In April 2017, Japan became the first country in the world to recognize Bitcoin as a legal method of payment 4. Australia is planning to follow soon 5. Such developments introduce new regulatory compliance requirements for financial institutions, businesses, individuals and the public sector. For instance, legally recognizing digital assets secured by a DLT as a payment method implies that compliance rules against money laundering also need to come into effect. This new state of affairs generates a conflict between decentralized, cross-national, and potentially anonymous transactions facilitated by DLT on the one side, and the need for their regulation and taxation at national-level jurisdictions on the other side. The underlying technologies themselves may currently render it difficult, if not infeasible, to implement certain regulatory requirements 6. Regulatory Technology or RegTech is a subclass of FinTech (i.e., Financial Technologies) and refers to the use of information technology in the context of regulatory monitoring, reporting, and compliance from which the finance industry benefits. How can RegTech cope efficiently with DLT-based assets and their underlying technologies? This project, PR4DLT, aims to address this question by performing basic research in the area of privacy-preserving regulatory technologies in the context of distributed ledgers to derive the appropriate theoretical and technical foundations for their practical application. Thereby, basic building blocks for future regulatory technologies are created that can serve as a starting point as well as a construction kit for implementing different compliance requirements in a secure and privacy-preserving way. PR4DLT addresses the question of how Blockchain- and Distributed Ledger Technologies can comply with potential future regulations from a technical viewpoint, while at the same time maintaining decentralization and privacy characteristics as far as possible.


Security and Privacy for Payment-Channel Networks

2019 – 2020 •  Austrian Science Fund (FWF)

Bitcoin sparked the blockchain ecosystem and has been followed by a plethora of blockchain approaches. Their growing expectations and usage is at odds with their scalability. Bitcoin today supports tens of transaction per second, a rate far from satisfactory to cater the current demand. Unfortunately, this is not an isolated symptom from Bitcoin but an epidemic problem with blockchain today. The most promising scalability solution today are payment channels: Two users leverage a single on-chain transaction to establish a shared deposit of coins. Subsequent payments are performed off-chain by agreeing on an updated deposits balance. Finally, only one additional on-chain transaction is required to close the deposit in the blockchain. Leveraging paths of payment channels, a payment-channel network allow any two users to pay each other. Unfortunately, current payment-channel networks at are their infancy and more work is required to bring them to minimum standards for mass adoption with proper security and privacy guarantees. In this state of affairs, the focus of this project is two-fold: (WP1) studying the theoretical possibilities and limits of payment-channel networks for mass adoption with sufficient security and privacy guarantees; (WP2) laying the foundations for payment-channel networks applications in order to release all their potential. WP1 is divided in three tasks: (a) set the foundations of security and privacy for payment channels. Simplified transaction formats augment the probability of success at providing security and privacy guarantees while reducing the amount of information to be stored at the blockchain. This is definitely a mandatory requirement given the current scalability issues; (b) set the foundations for offline users in payment-channel networks. Current approaches require that all users are always online, a requirement that clearly hinders their deployment in practice as users come and go as they please; (c) set the foundations of interoperable payment channels. Current isolated blockchains clearly restrict their potential. By providing interoperable protocols, we plan to release the whole potential of payment-channel networks. WP2 is also divided in three tasks: (a) build payment-channels secure against stronger adversaries such as quantum attackers; (b) build payment-channel networks over privacy-preserving cryptocurrencies such as Monero or Zcash, an open problem today that however would pave the way for better privacy guarantees; (c) build currency exchange protocols to support seamless exchanges of not only coins but any other good that can be represented in the blockchain, a main use case hindered today due to the isolation of different blockchains. Therefore, this project will provide the missing foundations and constructions to bring payment-channel networks into a solid state that can get mass adoption as scalability solution.


Scalability for Lightning Networks

2018 – 2020 •  Chaincode Labs Inc  •  PI Matteo Maffei

The Bitcoin blockchain provides a transaction rate of tens of transactions per second, far below what is needed to cater the growing number of transactions in the Bitcoin ecosystem. This constitutes a systematic scalability issue that is not unique to Bitcoin, as it is applicable to other blockchains as well. In this state of affairs, off-chain contracts have emerged as the most widely adopted scalability solution. Current deployments such as the Lightning Network have demonstrated that off-chain contracts (e.g., payment channels) can interact with each other to enable off-chain applications such as decentralized off-chain payments. Despite the indisputable advantages provided by off-chain contracts, they still present several challenges that are understudied and yet are crucial to successfully support off-chain applications. In this project, we plan to lay the foundations for off-chain contracts and study the possibilities and theoretical limits with this technology.


Ethertrust - Trustworthy smart contracts

2018 – 2019 •  •  PI Matteo Maffei

(German) Die Kryptowährung Ethereum erlaubt Nutzern neben der Tätigung von Finanztransaktionen auch die Ausführung beliebiger Programme so genannter smart contracts (ESC). Da ESC Finanzflüsse steuern, können Programmfehler schnell zu hohen Verlusten führen. Für den Nutzer sind solche Fehler oder sogar absichtlich implementierte schädliche Verhaltensweisen aus dem Code des Vertrages jedoch kaum ersichtlich. In unserer aktuellen Forschung entwickeln wir eine statische Analyse-Methode, die es erlaubt automatisch zu beweisen, dass ein ESC bestimmte schädliche Eigenschaften nicht besitzt. Aus dieser Methode entwickeln wir einen Online-Service, der es Nutzern von Ethereum ermöglicht ihre eigenen Verträge oder solche, mit denen sie interagieren wollen, automatisch zu analysieren. Unser Ziel ist ein intuitiv bedienbares Online-Tool, bei dem die Nutzer die betreffenden Verträge hochladen, aus einem Pool Eigenschaften wählen können und anschließend verständliche Analyseresultate erhalten.