Due to its large address space, IPv6 remains a challenge for Internet measurements. Thus, IPv6 scans often resort to hitlists that, however, mainly cover core Internet infrastructure and servers. Contrarily, a recent approach to source addresses leveraging NTP servers promises to discover more user-related hosts. Yet, an in-depth analysis of hosts found by this approach is missing and its impact remains unclear.

The increasing integration of decentralized renewable energy resources and the drive for greater efficiency have accelerated the transition from traditional power grids to smart grids. This shift necessitates robust communication architectures to ensure grid stability and prevent blackouts. Fast and reliable communication is especially critical for exchanging measurements and configurations in adaptive grid protection systems, which must be resilient to link and device failures. Allowing the use of multiple communication paths within a single TCP connection, Multipath TCP (MPTCP)'s benefits have been well-researched in other domains but its potential for smart grids remains unexplored. In this paper, we address this gap by conducting a large-scale emulation of a real electric power distribution system's communication network, incorporating context-specific hardware. Our evaluation shows the feasibility and benefits of MPTCP for realizing failovers in smart grids compared to TCP and QUIC and explores the trade-offs of MPTCP's default and redundant schedulers in terms of usability and performance.

Internet-wide studies provide extremely valuable insight into how operators manage their Internet of Things (IoT) deployments in reality and often reveal grievances, e.g., significant security issues. However, while IoT devices often use IPv6, past studies resorted to comprehensively scan the IPv4 address space. To fully understand how the IoT and all its services and devices is operated, including IPv6-reachable deployments is inevitable—although scanning the entire IPv6 address space is infeasible.In this paper, we close this gap and examine how to discover IPv6-reachable IoT deployments. Using three sources of active IPv6 addresses and eleven address generators, we discovered 6658 IoT deployments. We derive that the available address sources are a good starting point for finding IoT deployments. Additionally, we show that using two address generators is sufficient to cover most found deployments. Assessing the security of the deployments, we surprisingly find similar issues as in the IPv4 Internet, although IPv6 deployments might be newer and generally more up-to-date: Only 39% of deployments have access control in place and only 6.2% make use of TLS inviting attackers, e.g., to eavesdrop sensitive data.

Advances like Industry 4.0 lead to a rising number of Internet-connected industrial deployments and thus an Industrial Internet of Things with growing attack vectors. To uphold a secure and safe operation of these deployments, industrial protocols nowadays include security features, e.g., end-to-end secure communication. However, so far, it is unclear how well these features are used in practice and which obstacles might prevent operators from securely running their deployments.In this research description paper, we summarize our recent research activities to close this gap. Specifically, we show that even secure-by-design protocols are by far no guarantee for secure deployments. Instead, many deployments still open the doors for eavesdropping attacks or malicious takeovers. Additionally, we give an outlook on how to overcome identified obstacles allowing operators to configure their deployments more securely.

Containerization allows bundling applications and their dependencies into a single image. The containerization framework Docker eases the use of this concept and enables sharing images publicly, gaining high momentum. However, it can lead to users creating and sharing images that include private keys or API secrets—either by mistake or out of negligence. This leakage impairs the creator’s security and that of everyone using the image. Yet, the extent of this practice and how to counteract it remains unclear.

The evolving landscape of data ecosystems (DEs) increasingly demands integrated and collaborative data-sharing mechanisms that simultaneously ensure data sovereignty. However, recently proposed federated platforms, e.g., Gaia-X, only offer a promising solution to share data among already trusted participants-they still lack features to establish and maintain trust. To address this issue, we propose transparency logs for data usage that retrospectively build trust among participants. Inspired by certificate transparency logs that successfully bridge trust gaps in PKIs, we equip data owners with credible evidence of data usage. We show that our transparency logs for data usage are well scalable to sizable DEs. Thus, they are a promising approach to bridge trust gaps in federated DEs with cryptographic guarantees, fostering more robust data sharing.

Dynamic and flexible business relationships are expected to become more important in the future to accommodate specialized change requests or small-batch production. Today, buyers and sellers must disclose sensitive information on products upfront before the actual manufacturing. However, without a trust relation, this situation is precarious for the involved companies as they fear for their competitiveness. Related work overlooks this issue so far: existing approaches protect the information of a single party only, hindering dynamic and on-demand business relationships. To account for the corresponding research gap of inadequately privacy-protected information and to deal with companies without an established trust relation, we pursue the direction of innovative privacy-preserving purchase inquiries that seamlessly integrate into today’s established supplier management and procurement processes. Utilizing well-established building blocks from private computing, such as private set intersection and homomorphic encryption, we propose two designs with slightly different privacy and performance implications to securely realize purchase inquiries over the Internet. In particular, we allow buyers to consider more potential sellers without sharing sensitive information and relieve sellers of the burden of repeatedly preparing elaborate yet discarded offers. We demonstrate our approaches’ scalability using two real-world use cases from the domain of production technology. Overall, we present deployable designs that offer two-way privacy for purchase inquiries and, in turn, fill a gap that currently hinders establishing dynamic and flexible business relationships. In the future, we expect significantly increasing research activity in this overlooked area to address the needs of an evolving production landscape.

The ongoing trend to move industrial appliances from previously isolated networks to the Internet requires fundamental changes in security to uphold secure and safe operation. Consequently, to ensure end-to-end secure communication and authentication, (i) traditional industrial protocols, e.g., Modbus, are retrofitted with TLS support, and (ii) modern protocols, e.g., MQTT, are directly designed to use TLS. To understand whether these changes indeed lead to secure Industrial Internet of Things deployments, i.e., using TLS-based protocols, which are configured according to security best practices, we perform an Internet-wide security assessment of ten industrial protocols covering the complete IPv4 address space.

Nowadays, collaborations between industrial companies always go hand in hand with trust issues, i.e., exchanging valuable production data entails the risk of improper use of potentially sensitive information. Therefore, companies hesitate to offer their production data, e.g., process parameters that would allow other companies to establish new production lines faster, against a quid pro quo. Nevertheless, the expected benefits of industrial collaboration, data exchanges, and the utilization of external knowledge are significant.

Due to increasing digitalization, formerly isolated industrial networks, e.g., for factory and process automation, move closer and closer to the Internet, mandating secure communication. However, securely setting up OPC UA, the prime candidate for secure industrial communication, is challenging due to a large variety of insecure options. To study whether Internet-facing OPC UA appliances are configured securely, we actively scan the IPv4 address space for publicly reachable OPC UA systems and assess the security of their configurations. We observe problematic security configurations such as missing access control (on 24% of hosts), disabled security functionality (24%), or use of deprecated cryptographic primitives (25%) on in total 92% of the reachable deployments. Furthermore, we discover several hundred devices in multiple autonomous systems sharing the same security certificate, opening the door for impersonation attacks. Overall, in this paper, we highlight commonly found security misconfigurations and underline the importance of appropriate configuration for security-featuring protocols.

More and more traditional services, such as malware detectors or collaboration services in industrial scenarios, move to the cloud. However, this behavior poses a risk for the privacy of clients since these services are able to generate profiles containing very sensitive information, e.g., vulnerability information or collaboration partners. Hence, a rising need for protocols that enable clients to obtain knowledge without revealing their requests exists. To address this issue, we propose a protocol that enables clients (i) to query large cloud-based knowledge systems in a privacy-preserving manner using Private Set Intersection and (ii) to subsequently obtain individual knowledge items without leaking the client's requests via few Oblivious Transfers. With our preliminary design, we allow clients to save a significant amount of time in comparison to performing Oblivious Transfers only.

An increasing number of IoT scenarios involve mobile, resource-constrained IoT devices that rely on untrusted networks for Internet connectivity. In such environments, attackers can derive sensitive private information of IoT device owners, e.g., daily routines or secret supply chain procedures, when sniffing on IoT communication and linking IoT devices and owner. Furthermore, untrusted networks do not provide IoT devices with any protection against attacks from the Internet. Anonymous communication using onion routing provides a well-proven mechanism to keep the relationship between communication partners secret and (optionally) protect against network attacks. However, the application of onion routing is challenged by protocol incompatibilities and demanding cryptographic processing on constrained IoT devices, rendering its use infeasible. To close this gap, we tailor onion routing to the IoT by bridging protocol incompatibilities and offloading expensive cryptographic processing to a router or web server of the IoT device owner. Thus, we realize resource-conserving access control and end-to-end security for IoT devices. To prove applicability, we deploy onion routing for the IoT within the well-established Tor network enabling IoT devices to leverage its resources to achieve the same grade of anonymity as readily available to traditional devices.