TY - CHAP A1 - Saatjohann, Christoph A1 - Ising, Fabian A1 - Schinzel, Sebastian T1 - KIM: Kaos In der Medizin T2 - Sicherheit, Schutz und Zuverlässigkeit: Konferenzband der 12. Jahrestagung des Fachbereichs Sicherheit der Gesellschaft für Informatik e.V. (GI) N2 - Die sichere E-Mail-Infrastruktur für Ärzt*innen, Apotheker*innen, Krankenversicherungen und Kliniken in Deutschland, KIM - Kommunikation im Gesundheitswesen - ist mit über 200 Millionen E-Mails in den vergangenen zwei Jahren eine der am meisten genutzten Anwendungen in der Telematikinfrastruktur. Mit dem Ausgeben von S/MIME-Zertifikaten für alle medizinische Beteiligten in Deutschland verspricht KIM sichere Ende-zu-Ende-Verschlüsselung von E-Mails zwischen Heilberufler*innen in ganz Deutschland. In diesem Paper analysieren wir die KIM-Spezifikation sowie eine beispielhafte KIM-Installation in einer deutschen Zahnarztpraxis. Wir zeigen, dass KIM kryptografisch ein sehr hohes Sicherheitslevel erfüllt, doch in der Verarbeitung der E-Mails bei den Clients eine schwerwiegende Sicherheitslücke besteht. Weiterhin zeigen wir zwei Sicherheitslücken in dem KIM-Verarbeitungsmodul eines großen deutschen Unternehmens für medizinische Software. Diese Defizite zeigen außerdem Mängel in dem verpflichtenden Zulassungsprozess der KIM-Komponenten auf. Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:836-opus-178072 ER - TY - CHAP A1 - Völker, Timo A1 - Tüxen, Michael T1 - Packet Too Big Detection and its Integration into QUIC T2 - 2023 16th International Conference on Signal Processing and Communication System (ICSPCS) N2 - A communication over an Internet Protocol (IP) based network fails if an endpoint sends packets that are too big to reach their destination and if the sender is unable to detect that. The node on the path that drops these packets should respond with a Packet Too Big (PTB) message. However, multiple scenarios exist in which the sender will not receive a PTB message. Even if it does, it refrains from using the information in case it suspects that a potential attacker forged the message. In particular, we are not aware of any implementation of the secure transport protocol QUIC (e.g., used by HTTP/3) that processes PTB messages. In this paper, we present a novel parameterizable PTB detection algorithm for reliable transport protocols that does not depend on PTB messages. We further describe how to integrate our algorithm into QUIC, present results from an evaluation using the algorithm within a QUIC simulation model and, based on these results, suggest concrete parameter values. KW - PMTUD KW - PTB KW - black hole KW - transport protocol KW - QUIC Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:836-opus-174119 SN - 979-8-3503-3351-0 PB - IEEE CY - New York, NY, USA ER - TY - CHAP A1 - Salewski, Falk A1 - Bodenburg, Sven A1 - Malechka, Tatsiana ED - Jäkel, Jens ED - Reiff-Stephan, Jörg ED - Schwarz, Jens André T1 - Durchgängige Digitalisierung industrieller Abläufe am Beispiel der Modellfabrik der FH Münster T2 - Tagungsband AALE 2023 - Mit Automatisierung gegen den Klimawandel N2 - Die Modellfabrik der FH Münster erlaubt durch den Umfang und die Komplexität der enthaltenen Automatisierungsaufgaben sowie einen Aufbau aus industriellen Komponenten eine praxisnahe Lehre im Bereich aktueller Anlagenautomatisierung und darüber hinausgehenden Funktionen im Sinne einer durchgängigen Digitalisierung. Die verwendete Unterscheidung der durchgängigen Digitalisierung in horizontale und vertikale Verknüpfungen wird veranschaulicht. Aufbauend auf Erfahrungen mit der Vorgängeranlage werden Neuerungen der 2021 aufgebauten neuen Modellfabrik vorgestellt. Neuerungen umfassen insbesondere die Modularisierung der Anlage, das umgesetzte Sicherheitskonzept, einen Webshop mit Onlinekonfigurator, eine Webvisualiserung des Anlagenzustandes inklusive der Energieverbräuche, sowie Möglichkeiten zur virtuellen Inbetriebnahme. Weiterhin wird das aktuelle Konzept zur Erweiterung der horizontalen digitalen Durchgängigkeit mittels der Einbindung eines autonomen mobilen Roboters in die Modellfabrik vorgestellt. KW - Modellfabrik, Industrie 4.0, Cyber-Physical Systems, Durchgängige Digitalisierung, Autonomer mobiler Roboter, Lehre Y1 - 2023 UR - https://nbn-resolving.org/urn:nbn:de:bsz:l189-qucosa2-839648 SN - 978-3-910103-01-6 U6 - http://dx.doi.org/10.33968/2023.44 ER - TY - CHAP A1 - Ising, Fabian A1 - Poddebniak, Damian A1 - Kappert, Tobias A1 - Saatjohann, Christoph A1 - Schinzel, Sebastian T1 - Content-Type: multipart/oracle -- Tapping into Format Oracles in Email End-to-End Encryption T2 - 32nd USENIX Security Symposium N2 - S/MIME and OpenPGP use cryptographic constructions repeatedly shown to be vulnerable to format oracle attacks in protocols like TLS, SSH, or IKE. However, format oracle attacks in the End-to-End Encryption (E2EE) email setting are considered impractical as victims would need to open many attacker-modified emails and communicate the decryption result to the attacker. But is this really the case? In this paper, we survey how an attacker may remotely learn the decryption state in email E2EE. We analyze the interplay of MIME and IMAP and describe side-channels emerging from network patterns that leak the decryption status in Mail User Agents (MUAs). Concretely, we introduce specific MIME trees that produce decryption-dependent net work patterns when opened in a victim’s email client. We survey 19 OpenPGP- and S/MIME-enabled email clients and four cryptographic libraries and uncover a side-channel leaking the decryption status of S/MIME messages in one client. Further, we discuss why the exploitation in the other clients is impractical and show that it is due to missing feature support and implementation quirks. These unintended defenses create an unfortunate conflict between usability and security. We present more rigid countermeasures for MUA developers and the standards to prevent exploitation. Y1 - 2023 UR - https://www.usenix.org/conference/usenixsecurity23 PB - USENIX Association ER - TY - CHAP A1 - Mayer, Peter A1 - Poddebniak, Damian A1 - Fischer, Konstantin A1 - Brinkmann, Marcus A1 - Somorovsky, Juraj A1 - Schinzel, Sebastian A1 - Volkamer, Melanie T1 - "I don’t know why I check this...'' - Investigating Expert Users' Strategies to Detect Email Signature Spoofing Attacks T2 - Eighteenth Symposium on Usable Privacy and Security (SOUPS 2022) N2 - OpenPGP is one of the two major standards for end-to-end email security. Several studies showed that serious usability issues exist with tools implementing this standard. However, a widespread assumption is that expert users can handle these tools and detect signature spoofing attacks. We present a user study investigating expert users' strategies to detect signature spoofing attacks in Thunderbird. We observed 25 expert users while they classified eight emails as either having a legitimate signature or not. Studying expert users explicitly gives us an upper bound of attack detection rates of all users dealing with PGP signatures. 52% of participants fell for at least one out of four signature spoofing attacks. Overall, participants did not have an established strategy for evaluating email signature legitimacy. We observed our participants apply 23 different types of checks when inspecting signed emails, but only 8 of these checks tended to be useful in identifying the spoofed or invalid signatures. In performing their checks, participants were frequently startled, confused, or annoyed with the user interface, which they found supported them little. All these results paint a clear picture: Even expert users struggle to verify email signatures, usability issues in email security are not limited to novice users, and developers may need proper guidance on implementing email signature GUIs correctly. Y1 - 2022 UR - https://www.usenix.org/conference/soups2022/presentation/mayer SN - 978-1-939133-30-4 SP - 77 EP - 96 PB - USENIX Association CY - Boston, MA ER - TY - CHAP A1 - Löchte, Andre A1 - Thranow, Jan-Ole A1 - Winters, Felix A1 - Glösekötter, Peter T1 - Analysis of switching electronics for metal-air batterie T2 - ICECET, Prag N2 - The subject of this paper is the analysis of various switching electronics for batteries with separate electrodes for charging and discharging. The aim is to find a switching method that is energy-efficient on the one hand, but also economically viable on the other. Both relays and MOSFETs are suitable for switching between the electrodes. Both variants have advantages and disadvantages. The results show that a solution with MOSFETs is generally more energy-efficient, but requires a large number of cycles to be economically viable compared to the relay. KW - Analysis Y1 - 2022 U6 - http://dx.doi.org/10.1109/ICECET55527.2022.9872910 ER - TY - CHAP A1 - Saatjohann, Christoph A1 - Ising, Fabian A1 - Gierlings, Matthias A1 - Noss, Dominik A1 - Schimmler, Sascha A1 - Klemm, Alexander A1 - Grundmann, Leif A1 - Frosch, Tilman A1 - Schinzel, Sebastian T1 - Sicherheit medizintechnischer Protokolle im Krankenhaus T2 - SICHERHEIT 2022. Hrsg. Christian Wressnegger, Delphine Reinhardt, Thomas Barber, Bernhard C. Witt, Daniel Arp, Zoltan Mann N2 - Medizinische Einrichtungen waren in den letzten Jahren immer wieder von Cyber-Angriffen betroffen. Auch wenn sich diese Angriffe derzeit auf die Office-IT-Infrastruktur der Einrichtungen konzentrieren, existiert mit medizinischen Systemen und Kommunikationsprotokollen eine weitere wenig beachtete Angriffsoberfläche. In diesem Beitrag analysieren wir die weit verbreiteten medizintechnischen Kommunikations-Protokolle DICOM und HL7 sowie Protokoll-Implementierungen auf ihre IT-Sicherheit. Dafür präsentieren wir die Ergebnisse der Sicherheitsanalyse der DICOM- und HL7-Standards, einen Fuzzer “MedFUZZ” für diese Protokolle sowie einen Schwachstellenscanner “MedVAS”, der Schwachstellen in medizintechnischen Produktivumgebungen auffinden kann. Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:836-opus-150072 SN - 978-3-88579-717-3 SN - 1617-5468 PB - Gesellschaft für Informatik e.V. CY - Bonn ER - TY - CHAP A1 - Völker, Timo A1 - Volodina, Ekaterina A1 - Tüxen, Michael A1 - Rathgeb, Erwin Paul T1 - A QUIC Simulation Model for INET and its Application to the Acknowledgment Ratio Issue T2 - 2020 IFIP Networking Conference N2 - Quick UDP Internet Connections (QUIC) is a novel transport protocol introducing known features in a new protocol design. To investigate these features and the design, we developed a QUIC implementation in the INET simulation model suite. In this paper, we describe that implementation, its validation and a result achieved using the simulation model. The result shows the negative impact on throughput, when raising the acknowledgment ratio. We propose a solution and describe how it solves the issue. KW - QUIC KW - INET OMNeT++ KW - Protocol Simulation KW - Transport Protocol KW - Ack Ratio Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:836-opus-149662 UR - https://ieeexplore.ieee.org/document/9142723 SN - 978-3-903176-28-7 SP - 737 EP - 742 PB - IEEE CY - New York, NY, USA ER - TY - CHAP A1 - Völker, Timo A1 - Tüxen, Michael A1 - Rathgeb, Erwin Paul T1 - The Search of the Path MTU with QUIC T2 - Proceedings of the 2021 Workshop on Evolution, Performance and Interoperability of QUIC N2 - A data sender in an IP based network is only capable to efficiently use a network path if it knows the packet size limit of the path, i.e., the Path Maximum Transmission Unit (PMTU). The IETF recently specified a PMTU discovery framework for transport protocols like QUIC. This paper complements this specification by presenting a search algorithm. In addition, it defines several metrics and shows results of analyses for the algorithm with various PMTU candidate sequences using these metrics. We integrated the PMTU discovery with our algorithm into a QUIC simulation model. This paper describes the integration and presents measurements obtained by simulations. KW - Path MTU Discovery KW - Search Algorithm KW - Simulation KW - Transport Protocol KW - QUIC Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:836-opus-149656 SN - 9781450391351 SP - 22 EP - 28 PB - Association for Computing Machinery CY - New York, NY, USA ER - TY - CHAP A1 - Rörup, Tim A1 - Glösekötter, Peter A1 - Pomares, Hector A1 - Ruiz, Ignacio T1 - Deep Learning Based Neural Network for Six-Class-Classification of Alzheimer's Disease Stages Based on MRI Images T2 - IWANN2021 N2 - State of the art classifiers split Alzheimer’s disease progression into a limited number of stages and use a comparatively small database. For the best treatment, it is desirable to have the highest resolution from the progression of the disease. This paper proposes a reliable deep convolutional neural network for the classification of six different Alzheimer’s disease stages based on Magnetic Resonance Imaging (MRI). The peculiarity of this paper is the introduction of a new, sixth, disease stage, and the large amount of data that has been taken into account. Additionally, not only the testing accuracy is analyzed, but also the robustness of the classifier to have feedback on how certain the neural network makes its predictions. KW - Deep Learning Y1 - 2021 U6 - http://dx.doi.org/10.1007/978-3-030-85030-2_1 SP - 3 EP - 14 PB - Springer International Publishing ER - TY - CHAP A1 - Gómez Zuluaga, Mauricio Andrés A1 - Ordikhani, Ahmad A1 - Bauer, Christoph A1 - Glösekötter, Peter T1 - Development and implementation of a neural network-based abnormal state prediction system for a piston pump T2 - IWANN2021 N2 - Piston pumps play a key role in factory automation and their availability is very critical for the smooth running of production processes. Modern installations, such as production plants and machines, are becoming increasingly complex. Therefore, the probability of a complete system failure due to a single critical component also increases. Maintenance processes with intelligent devices are therefore very important to achieve maximum economic efficiency and safety. Periodic or continuous monitoring of system components provides key information about the current physical state of the system, enabling early detection of emerging failures. Knowledge of future failures makes it possible to move from the concept of preventive maintenance to intelligent predictive maintenance. In this way, consequential damage and complete system failure can be avoided, maximizing system availability and safety. This paper reflects the development and implementation of a neural network system for abnormal state prediction of piston pumps. After a short introduction into piston pumps and their potential abnormal states, statistical and periodical analysis are presented. Then the design and implementation of suitable neural networks are discussed. Finally, a conclusion is drawn and the observed accuracies as well as potential next steps are discussed. KW - Development and implementation Y1 - 2021 SN - 978-3-030-85029-6 U6 - http://dx.doi.org/10.1007/978-3-030-85030-2_24 PB - Springer Nature Switzerland AG 2021 ER - TY - CHAP A1 - Willing, Markus A1 - Saatjohann, Christoph A1 - Rath, Benjamin A1 - Schinzel, Sebastian A1 - Eckardt, Lars A1 - Köbe, Julia T1 - Experiences with General Data Protection Regulations and Remote Monitoring of Implantable Rhythm Devices T2 - 87. Jahrestagung der Deutsche Gesellschaft für Kardiologie – Herz‑ und Kreislauforschung e.V Y1 - 2021 U6 - http://dx.doi.org/10.1007/s00392-021-01843-w PB - Springer-Verlag GmbH ER - TY - CHAP A1 - Ebbers, Simon A1 - Ising, Fabian A1 - Saatjohann, Christoph A1 - Schinzel, Sebastian T1 - Grand Theft App: Digital Forensics of Vehicle Assistant Apps T2 - ARES 2021: The 16th International Conference on Availability, Reliability and Security N2 - Due to the increasing connectivity of modern vehicles, collected data is no longer only stored in the vehicle itself but also transmitted to car manufacturers and vehicle assistant apps. This development opens up new possibilities for digital forensics in criminal investigations involving modern vehicles. This paper deals with the digital forensic analysis of vehicle assistant apps of eight car manufacturers. We reconstruct the driver’s activities based on the data stored on the smartphones and in the manufacturer’s backend. For this purpose, data of the Android and iOS apps of the car manufacturers Audi, BMW, Ford, Mercedes, Opel, Seat, Tesla, and Volkswagen were extracted from the smartphone and examined using digital forensic methods following forensics guidelines. Additionally, manufacturer data was retrieved using Subject Access Requests. Using the extensive data gathered, we reconstruct trips and refueling processes, determine parking positions and duration, and track the locking and unlocking of the vehicle. Our findings show that the digital forensic investigation of smartphone applications is a useful addition to vehicle forensics and should therefore be taken into account in the strategic preparation of future digital forensic investigations. Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:836-opus-139031 ER - TY - CHAP A1 - Puschner, Endres A1 - Saatjohann, Christoph A1 - Willing, Markus A1 - Dresen, Christian A1 - Köbe, Julia A1 - Rath, Benjamin A1 - Paar, Christof A1 - Eckardt, Lars A1 - Haverkamp, Uwe A1 - Schinzel, Sebastian T1 - Listen to Your Heart: Evaluation of the Cardiologic Ecosystem T2 - ARES 2021: The 16th International Conference on Availability, Reliability and Security N2 - Modern implantable cardiologic devices communicate via radio frequency techniques and nearby gateways to a backend server on the internet. Those implanted devices, gateways, and servers form an ecosystem of proprietary hardware and protocols that process sensitive medical data and is often vital for patients’ health. This paper analyzes the security of this Ecosystem, from technical gateway aspects, via the programmer, to configure the implanted device, up to the processing of personal medical data from large cardiological device producers. Based on a real-world attacker model, we evaluated different devices and found several severe vulnerabilities. Furthermore, we could purchase a fully functional programmer for implantable cardiological devices, allowing us to re-program such devices or even induce electric shocks on untampered implanted devices. Additionally, we sent several Art. 15 and Art. 20 GDPR inquiries to manufacturers of implantable cardiologic devices, revealing non-conforming processes and a lack of awareness about patients’ rights and companies’ obligations. This, and the fact that many vulnerabilities are still to be found after many vulnerability disclosures in recent years, present a worrying security state of the whole ecosystem. Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:836-opus-139012 ER - TY - CHAP A1 - Poddebniak, Damian A1 - Ising, Fabian A1 - Böck, Hanno A1 - Schinzel, Sebastian T1 - Why TLS is better without STARTTLS: A Security Analysis of STARTTLS in the Email Context T2 - Proceedings of the 30th USENIX Security Symposium, August 11–13, 2021 N2 - TLS is one of today's most widely used and best-analyzed encryption technologies. However, for historical reasons, TLS for email protocols is often not used directly but negotiated via STARTTLS. This additional negotiation adds complexity and was prone to security vulnerabilities such as naive STARTTLS stripping or command injection attacks in the past. We perform the first structured analysis of STARTTLS in SMTP, POP3, and IMAP and introduce EAST, a semi-automatic testing toolkit with more than 100 test cases covering a wide range of variants of STARTTLS stripping, command and response injections, tampering attacks, and UI spoofing attacks for email protocols. Our analysis focuses on the confidentiality and integrity of email submission (email client to SMTP server) and email retrieval (email client to POP3 or IMAP server). While some of our findings are also relevant for email transport (from one SMTP server to another), the security implications in email submission and retrieval are more critical because these connections involve not only individual email messages but also user credentials that allow access to a user's email archive. We used EAST to analyze 28 email clients and 23 servers. In total, we reported over 40 STARTTLS issues, some of which allow mailbox spoofing, credential stealing, and even the hosting of HTTPS with a cross-protocol attack on IMAP. We conducted an Internet-wide scan for the particularly dangerous command injection attack and found that 320.000 email servers (2% of all email servers) are affected. Surprisingly, several clients were vulnerable to STARTTLS stripping attacks. In total, only 3 out of 28 clients did not show any STARTTLS-specific security issues. Even though the command injection attack received multiple CVEs in the past, EAST detected eight new instances of this problem. In total, only 7 out of 23 tested servers were never affected by this issue. We conclude that STARTTLS is error-prone to implement, under-specified in the standards, and should be avoided. Y1 - 2021 UR - https://www.usenix.org/conference/usenixsecurity21/presentation/poddebniak SN - 978-1-939133-24-3 VL - 2021 ER - TY - CHAP A1 - Wansing, Christian A1 - Banos, Oresti A1 - Pomares, Hector A1 - Glösekötter, Peter A1 - Rojas Ruiz, Ignacio ED - Junta de Andalucia Project P12-TIC-2082., Conference Paper T1 - Development of a platform for the exchange of biodatasets with integrated opportunities for artificial intelligence using MatLab N2 - This paper deals with the issue of automating the process of machine learning and analyzing bio-datasets. For this a user-friendly website has been developed for the interaction with the researchers. On this website it is possible to upload datasets and to share them, if desired, with other scientists. The uploaded data can also be analyzed by various methods and functions. The signals inside these datasets can also be visualized. Furthermore several algorithms have been implemented to create machine learning models with the uploaded data. Based on these generated models new data can be classified or calculated. For all these applications the simplest possible handling was implemented to make the website available to all interested researchers. KW - M-health, machine learning, website Y1 - 2015 U6 - http://dx.doi.org/10.1109/ICoCS.2015.7483278 SP - 1 EP - 6 ER - TY - CHAP A1 - Horsthemke, Ludwig A1 - Bischoff, Christian A1 - Glösekötter, Peter A1 - Burchard, Bernd A1 - Staacke, Robert A1 - Meijer, Jan T1 - All optical readout scheme for photoluminescence based magnetic field sensors T2 - 2020 IEEE Sensors, Rotterdam, Netherlands N2 - An improvement on a concept for all optical mag- netometry using nitrogen vacancies in diamond is presented. The concept is based on the fluorescence attenuation of optically pumped nitrogen vacancies by magnetic fields up to ≈ 50 mT. The attenuation is registered by modulating the pumping power to generate a constant signal at a photodetector. A sensitivity of 2.6μT/√Hz at a sampling frequency of 500 Hz is achieved. KW - photoluminescence based magnetic field sensors Y1 - 2020 U6 - http://dx.doi.org/10.1109/SENSORS47125.2020.9278923 SP - 1 EP - 3 ER - TY - CHAP A1 - Willing, Markus A1 - Dresen, Christian A1 - Haverkamp, Uwe A1 - Schinzel, Sebastian T1 - Analyzing medical device connectivity and its effect on cyber security in german hospitals N2 - Background: Modern healthcare devices can be connected to computer networks and many western healthcareinstitutions run those devices in networks. At the same time, cyber attacks are on the rise and there is evidence thatcybercriminals do not spare critical infrastructure such as major hospitals, even if they endanger patients. Intuitively,the more and closer connected healthcare devices are to public networks, the higher the risk of getting attacked. Methods: To asses the current connectivity status of healthcare devices, we surveyed the field of German hospitalsand especially University Medical Center UMCs. Results: The results show a strong correlation between the networking degree and the number of medical devices.The average number of medical devices is 25.150, with a median of networked medical devices of 3.600. Actual keyusers of networked medical devices are the departments Radiology, Intensive Care, Radio-Oncology RO, NuclearMedicine NUC, and Anaesthesiology in the group of UMCs. In the next five years, the usage of networked medicaldevices will increase significantly in the departments of Surgery, Intensive Care, and Radiology. We detected a strongcorrelation between the degree of connectivity and the likelihood of being attacked.The survey answers regarding the cyber security status reveal a lack of security basics in some of the inquiredhospitals. We did discover successful attacks in hospitals with separated or subsidiary departments. A fusion ofcompetencies on an organizational level facilitates the right behavior here. Most hospitals rated themselvespredominantly positively in the self-assessment but also stated the usefulness of IT security insurance.Conclusions:Concluding our results, hospitals are already facing the consequences of omitted measures within theirgrowing pool of medical devices. Continuously relying on historically grown structures without adaption and trustingmanufactures to solve vectors is a critical behavior that could seriously endanger patients. Y1 - 2020 U6 - http://dx.doi.org/10.1186/s12911-020-01259-y PB - BMC Medical Informatics and Decision Making volume ER - TY - CHAP A1 - Müller, Jens A1 - Ising, Fabian A1 - Mla­de­nov, Vla­dis­lav A1 - Mainka, Chris­ti­an A1 - Schinzel, Sebastian A1 - Schwenk, Jörg T1 - Of­fice Do­cu­ment Se­cu­ri­ty and Pri­va­cy T2 - 14th USE­NIX Work­shop on Of­fen­si­ve Tech­no­lo­gies (WOOT 2020) N2 - OOXML and ODF are the de facto standard data formats for word processing, spreadsheets, and presentations. Both are XML-based, feature-rich container formats dating back to the early 2000s. In this work, we present a systematic analysis of the capabilities of malicious office documents. Instead of focusing on implementation bugs, we abuse legitimate features of the OOXML and ODF specifications. We categorize our attacks into five classes: (1) Denial-of-Service attacks affecting the host on which the document is processed. (2) Invasion of privacy attacks that track the usage of the document. (3) Information disclosure attacks exfiltrating personal data out of the victim's computer. (4) Data manipulation on the victim's system. (5) Code execution on the victim's machine. We evaluated the reference implementations – Microsoft Office and LibreOffice – and found both of them to be vulnerable to each tested class of attacks. Finally, we propose mitigation strategies to counter these attacks. KW - Cyber Security KW - Open Document Format KW - docx Y1 - 2020 UR - https://www.usenix.org/conference/woot20/presentation/muller PB - USENIX ER - TY - CHAP A1 - Müller, Jens A1 - Brinkmann, Marcus A1 - Poddebniak, Damian A1 - Schinzel, Sebastian A1 - Schwenk, Jörg T1 - Mailto: Me Your Secrets. On Bugs and Features in Email End-to-End Encryption T2 - 2020 IEEE Conference on Communications and Network Security (CNS) N2 - OpenPGP and S/MIME are the two major standards for email end-to-end encryption. We show practical attacks against both encryption schemes in the context of email. First, we present a design flaw in the key update mechanism, allowing a third party to deploy a new key to the communication partners. Second, we show how email clients can be tricked into acting as an oracle for decryption or signing by exploiting their functionality to auto-save drafts. Third, we demonstrate how to exfiltrate the private key, based on proprietary mailto parameters implemented by various email clients. An evaluation shows that 8 out of 20 tested email clients are vulnerable to at least one attack. While our attacks do not target the underlying cryptographic primitives, they raise concerns about the practical security of OpenPGP and S/MIME email applications. Finally, we propose countermeasures and discuss their advantages and disadvantages. KW - Cyber Security KW - PGP KW - S/MIME Y1 - 2020 U6 - http://dx.doi.org/10.1109/CNS48642.2020.9162218 SP - 1 EP - 9 ER - TY - CHAP A1 - Gierling, Markus A1 - Dresen, Christian A1 - Eich, Hans A1 - Mittman, Karin A1 - Schinzel, Sebastian A1 - Haverkamp, Uwe T1 - Analysis and consequences of an imaging process concerning the cyber security of a networked computer tomography scanner T2 - STRAHLENTHERAPIE UND ONKOLOGIE KW - Cyber Security KW - networked computer tomography scanner Y1 - 2018 SP - 185 EP - 186 ER - TY - CHAP A1 - Saatjohann, Christoph A1 - Ising, Fabian A1 - Krings, Luise A1 - Schinzel, Sebastian T1 - STALK: security analysis of smartwatches for kids T2 - ARES 2020: The 15th International Conference on Availability, Reliability and Security / Editors: Melanie Volkamer, Christian Wressnegger N2 - Smart wearable devices become more and more prevalent in the age of the Internet of Things. While people wear them as fitness trackers or full-fledged smartphones, they also come in unique versions as smartwatches for children. These watches allow parents to track the location of their children in real-time and offer a communication channel between parent and child. In this paper, we analyzed six smartwatches for children and the corresponding backend platforms and applications for security and privacy concerns. We structure our analysis in distinct attacker scenarios and collect and describe related literature outside academic publications. Using a cellular network Man-in-the-Middle setup, reverse engineering, and dynamic analysis, we found several severe security issues, allowing for sensitive data disclosure, complete watch takeover, and illegal remote monitoring functionality. KW - Security KW - Privacy Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:836-opus-123548 SN - 978-1-4503-8833-7 SP - 1 EP - 10 ER - TY - CHAP A1 - Horsthemke, Ludwig A1 - Staake, Robert A1 - Burchard, Bernd A1 - Meijer, Jan A1 - Bischoff, Christian A1 - Glösekötter, Peter T1 - Highly Sensitive Compact Room Temperature Quantum Scalar Magnetormeter T2 - SMSI 2020 N2 - Magnetometry with nitrogen–vacancy (NV) defects in diamond has been extensively stud-ied in the past [1]. While most approaches in-clude the use of microwaves (MW) for the de-tection of electron spin resonance, only few investigate the sensitivity of the photolumines-cence (PL) from NV centers to an external magnetic field without MW [2, 3, 4]. This work aims to utilize this effect to build a highly sensi-tive and compact room temperature magne-tometer. The avoidance of MW serves the re-duction of production costs and allows a com-mercialization at the current patent situation. KW - Highly Sensitive Y1 - 2020 U6 - http://dx.doi.org/10.5162/SMSI2020/A1.4 SP - 47 EP - 48 ER - TY - CHAP A1 - Glösekötter, Peter T1 - Hochintegrierte Mikro- und Nanosystem T2 - Workshop Nanotechnologie-Verbund NRW e.V. N2 - Die Beiträge, der Konferenz: • Nanotechnologie –Von Wunder-Materialien und solchen die es werden wollen • Mikrotechnik –to improve the qualityof live • Quantum Sensing for Industrial Applications • Geordnete Defekte in Graphit: Ein Fahrplan in Richtung Raumtemperatur Supraleitung • Funktionale mikro-und nanostrukturierte Folien als Bestandteil hochintegrierter Systeme KW - Hochintegrierte Mikro- und Nanosysteme Y1 - 2019 ER - TY - CHAP A1 - Dresen, Christian A1 - Ising, Fabian A1 - Poddebniak, Damian A1 - Kappert, Tobias A1 - Holz, Thorsten A1 - Schinzel, Sebastian ED - Zhou, Jianying T1 - CORSICA: Cross-Origin Web Service Identification T2 - The 15th ACM ASIA Conference on Computer and Communications Security N2 - Vulnerabilities in private networks are difficult to detect for attackers outside of the network. While there are known methods for port scanning internal hosts that work by luring unwitting internal users to an external web page that hosts malicious JavaScript code, no such method for detailed and precise service identification is known. The reason is that the Same Origin Policy (SOP) prevents access to HTTP responses of other origins by default. We perform a structured analysis of loopholes in the SOP that can be used to identify web applications across network boundaries. For this, we analyze HTML5, CSS, and JavaScript features of standard-compliant web browsers that may leak sensitive information about cross-origin content. The results reveal several novel techniques, including leaking JavaScript function names or styles of cross-origin requests that are available in all common browsers. We implement and test these techniques in a tool called CORSICA. It can successfully identify 31 of 42 (74%) of web services running on different IoT devices as well as the version numbers of the four most widely used content management systems WordPress, Drupal, Joomla, and TYPO3. CORSICA can also determine the patch level on average down to three versions (WordPress), six versions (Drupal), two versions (Joomla), and four versions (TYPO3) with only ten requests on average. Furthermore, CORSICA is able to identify 48 WordPress plugins containing 65 vulnerabilities. Finally, we analyze mitigation strategies and show that the proposed but not yet implemented strategies Cross-Origin Resource Policy (CORP)} and Sec-Metadata would prevent our identification techniques. Y1 - 2020 UR - https://asiaccs2020.cs.nthu.edu.tw/program/ ER - TY - CHAP A1 - Heller, Andreas A1 - Horsthemke, Ludwig A1 - Glösekötter, Peter T1 - Design, Implementation, and Evaluation of a Real Time Localization System for the Optimization of Agitation Processes T2 - IESS, Friedrichshafen N2 - This work describes the setup of an ultrawideband (UWB) realtime localization system (RTLS) for tracking of particles.We describe how the RTLS obtains distances and positions through radio waves and the setup and evaluation of a real world system is stated in detail. In the proposed system the particles track a subtrates surface ow inside a biogas plant for veri� cation of agitation processes. KW - UWB - RTLS - Biogas plant optimization Y1 - 2019 ER - TY - CHAP A1 - Heller, Andreas A1 - Horsthemke, Ludwig A1 - Gebing, Marcel A1 - Kappen, Götz A1 - Glösekötter, Peter T1 - GNSS based Automatic Anchor Positioning in Real Time Localization Systems T2 - Proceedings ITISE-2019. Granada, 25th-27th September 2019 N2 - This work describes the setup of an ultrawideband (UWB) realtime localization system (RTLS) in which the determination of anchor coordinates is automated by assistance of global navigation satellite systems (GNSS). KW - GNSS Y1 - 2019 SN - 978-84-17970-78-9 SP - 1068 EP - 1073 CY - Granada (Spain) ER - TY - CHAP A1 - Löchte, Andre A1 - Gebert, Ole A1 - Glösekötter, Peter T1 - End of charge detection of batteries with high production tolerances T2 - Proceedings ITISE-2019. Granada, 25th-27th September 2019 N2 - When developing new battery technologies, fundamental research means assembling new batteries by hand since a production line is not worthwhile for building and testing individual cells. This causes high production tolerances to occur because manual manufacturing is not as precise as machine-made. When putting these prototypes into operation, problems can arise due to the varying parameters. One of the most important exercise is finding a criterion of a full battery. This can be challenging when parameters like the capacity or the end of charge voltage are not precisely known due to the tolerances. Furthermore, new battery types do not necessarily rely on the same stopping criteria. For example zinc-air secondary batteries do not offer an end of charging voltage. Its charging current is not going to decrease when the battery is full and the charging voltage is held at a fixed value. But instead of de-oxidising zinc oxide, hydrogen is produced. In the majority of cases overcharging should be avoided as it harms the battery. Another even more dangerous consequence is the possibility of an explosion. Especially lithium based batteries are known for their need of compatible ambient and charging parameters. This paper proposes a new criterion for detecting the end of charge that is based on the rate of change of electrochemical impedance spectra of the examined batteries. Device parameter fluctuations influence every measurement. Therefore, using the rate of change offers the possibility to not depend on these fluctuations. KW - End of charge Y1 - 2019 SN - 978-84-17970-78-9 SP - 554 EP - 559 CY - Granada (Spain) ER - TY - CHAP A1 - Müller, Jens A1 - Ising, Fabian A1 - Mldadenov, Vladislav A1 - Mainka, Christian A1 - Schinzel, Sebastian A1 - Schwenk, Jörg T1 - Practical Decryption exFiltration: Breaking PDF Encryption T2 - The 26th ACM Conference on Computer and Communications, Security (CCS 2019), London, United Kingdom N2 - The Portable Document Format, better known as PDF, is one of themost widely used document formats worldwide, and in order to en-sure information confidentiality, this file format supports documentencryption. In this paper, we analyze PDF encryption and showtwo novel techniques for breaking the confidentiality of encrypteddocuments. First, we abuse the PDF feature ofpartially encrypteddocuments to wrap the encrypted part of the document withinattacker-controlled content and therefore, exfiltrate the plaintextonce the document is opened by a legitimate user. Second, we abusea flaw in the PDF encryption specification to arbitrarily manipulateencrypted content. The only requirement is that a single block ofknown plaintext is needed, and we show that this is fulfilled bydesign. Our attacks allow the recovery of the entire plaintext of en-crypted documents by using exfiltration channels which are basedon standard compliant PDF properties.We evaluated our attacks on 27 widely used PDF viewers andfound all of them to be vulnerable. We responsibly disclosed thevulnerabilities and supported the vendors in fixing the issue Y1 - 2019 UR - https://pdf-insecurity.org/download/paper-pdf_encryption-ccs2019.pdf U6 - http://dx.doi.org/10.1145/3319535.3354214 ER - TY - CHAP A1 - Müller, Jens A1 - Brinkmann, Marcus A1 - Poddebniak, Damian A1 - Schinzel, Sebastian A1 - Schwenk, Jörg T1 - What's up John­ny? – Co­vert Con­tent At­tacks on Email End-to-End En­cryp­ti­on T2 - 17th In­ter­na­tio­nal Con­fe­rence on Ap­p­lied Cryp­to­gra­phy and Net­work Se­cu­ri­ty (ACNS 2019) N2 - We show practical attacks against OpenPGP and S/MIMEencryption and digital signatures in the context of email. Instead of tar-geting the underlying cryptographic primitives, our attacks abuse legiti-mate features of the MIME standard and HTML, as supported by emailclients, to deceive the user regarding the actual message content. Wedemonstrate how the attacker can unknowingly abuse the user as a de-cryption oracle by replying to an unsuspicious looking email. Using thistechnique, the plaintext of hundreds of encrypted emails can be leakedat once. Furthermore, we show how users could be tricked into signingarbitrary text by replying to emails containing CSS conditional rules.An evaluation shows that "out of" OpenPGP-capable email clients,as well as "out of" clients supporting S/MIME, are vulnerable to atleast one attack. We provide different countermeasures and discuss theiradvantages and disadvantages. Y1 - 2019 SP - 1 EP - 18 ER - TY - CHAP A1 - Müller, Jens A1 - Brinkmann, Marcus A1 - Poddebniak, Damian A1 - Böck, Hanno A1 - Schinzel, Sebastian A1 - Smomrosvsky, Juraj A1 - Schwenk, Jörg T1 - “Johnny, you are fired!” – Spoofing OpenPGP and S/MIME Signatures in Emails T2 - 28th Usenix Security Symposium, Santa Clara, CA, USA N2 - OpenPGP and S/MIME are the two major standards to en-crypt and digitally sign emails. Digital signatures are sup-posed to guarantee authenticity and integrity of messages. Inthis work we show practical forgery attacks against variousimplementations of OpenPGP and S/MIME email signatureverification in five attack classes: (1) We analyze edge casesin S/MIME’s container format. (2) We exploit in-band sig-naling in the GnuPG API, the most widely used OpenPGPimplementation. (3) We apply MIME wrapping attacks thatabuse the email clients’ handling of partially signed mes-sages. (4) We analyze weaknesses in the binding of signedmessages to the sender identity. (5) We systematically testemail clients for UI redressing attacks.Our attacks allow the spoofing of digital signatures for ar-bitrary messages in 14 out of 20 tested OpenPGP-capableemail clients and 15 out of 22 email clients supportingS/MIME signatures. While the attacks do not target the un-derlying cryptographic primitives of digital signatures, theyraise concerns about the actual security of OpenPGP andS/MIME email applications. Finally, we propose mitigationstrategies to counter these attacks. Y1 - 2019 UR - https://www.usenix.org/conference/usenixsecurity19/presentation/muller EP - 18 ER - TY - CHAP A1 - Löchte, Andre A1 - Gebert, Ole A1 - Heming, Daniel A1 - Kallis, Klaus A1 - Glösekötter, Peter ED - Springer, Axel T1 - State estimation of zinc air batteries using neural networks T2 - IWANN 2017: Advances in Computational Intelligence N2 - The main task of battery management systems is to keep the working area of the battery in a safe state. Estimation of the state of charge and the state of health is therefore essential. The traditional way uses the voltage level of a battery to determine those values. Modern metal air batteries provide a flat voltage characteristic which necessitates new approaches. One promising technique is the electrochemical impedance spectroscopy, which measures the AC resistance for a set of different frequencies. Previous approaches match the measured impedances with a nonlinear equivalent circuit, which needs a lot of time to solve a nonlinear least-squares problem. This paper combines the electrochemical impedance spectroscopy with neural networks to speed up the state estimation using the example of zinc air batteries. Moreover, these networks are trained with different subsets of the spectra as input data in order to determine the required number of frequencies. Y1 - 2018 U6 - http://dx.doi.org/10.1007/s00521-018-3705-9 SN - 0941-0643 VL - 2018 SP - 1 EP - 9 ER - TY - CHAP A1 - Löchte, Andre A1 - Gebert, Ole A1 - Horsthemke, Ludwig A1 - Heming, Daniel A1 - Glösekötter, Peter T1 - State of Charge Depended Modeling of an Equivalent Circuit of Zinc Air Batteries Using Electrochemical Impedance Spectroscopy T2 - International Conference on Time Series and Forecasting: Proceedings of Papers, 19-21 September 2018, Granada (Spain) N2 - Metal air batteries provide a high energy density as the ca-thodic reaction uses the surrounding air. Different metals can be usedbut zinc is very promising due to its disposability and nontoxic behav-ior. State estimation is quite complicated as the voltage characteristicof the battery is rather flat. Especially estimating the state of chargeis important as a secondary electrolysis process during overcharging canlead to an unsafe state. Another technique for state estimation is theelectrochemical impedance spectroscopy. Therefore, this paper describesthe process of setup and measuring a time series of impedance spectraat known states of charge. Then these spectra are used to derive anequivalent circuit. Finally the development of the circuit’s parameter areanalyzed to extract most important parameters. Y1 - 2018 SN - 978-84-17293-57-4 SP - 625 EP - 636 ER - TY - CHAP A1 - Burke, Bruno A1 - Weßeler, Peter A1 - te Vrugt, Jürgen ED - Pammer-Schindler, Viktoria ED - Pérez-Sanagustín, Mar ED - Drachsler, Hendrik ED - Elferink, Raymond ED - Scheffel, Maren T1 - A Programming Language Independent Platform for Algorithm Learning T2 - Lifelong Technology-Enhanced Learning, 13th European Conference on Technology Enhanced Learning. EC-TEL 2018 N2 - Teaching People to program is a crucial requirement for our society to deal with the complexity of 21st-century challenges. In many teaching systems, the student is required to use a particular programming language or development environment. This paper presents an intelligent tutoring system to support blended learning scenarios, where the students can choose their programming language and development environment. For that, the system provides an interface where the students request test data and submit results to unit test their algorithms. The submitted results are analyzed by a machine learning system that detects common errors and provides adaptive feedback to the student. With this system, we are focusing on teaching algorithms rather than specific programming language semantics. The technical evaluation tested with the implementation of Mean and Median algorithm shows that the system can distinguish between error cases with an error rate under 20%. A first survey, with a small group of students, shows that the system helps them detect common errors and arrive at a correct/valid solution. We are in the process of testing the system with a larger group of students for gathering statistically reliable data. KW - Language-independent programming KW - Tutoring system KW - Algorithm learning Y1 - 2018 UR - https://link.springer.com/chapter/10.1007%2F978-3-319-98572-5_66 SN - 978-3-319-98572-5 U6 - http://dx.doi.org/10.1007/978-3-319-98572-5_66 SP - 652 EP - 655 PB - Springer, Cham ER - TY - CHAP A1 - Weβeler, Peter A1 - Kaiser, Benjamin A1 - te Vrugt, Jürgen A1 - Lechler, Armin A1 - Verl, Alexander T1 - Camera based path planning for low quantity - high variant manufacturing with industrial robots T2 - 25th International Conference on Mechatronics and Machine Vision in Practice (M2VIP) N2 - The acquisition costs for industrial robots have been steadily decreasing in past years. Nevertheless, they still face significant drawbacks in the required effort for the preparation of complex robot tasks which causes these systems to be rarely present so far in small and medium-sized enterprises (SME) that focus mainly on small volume, high variant manufacturing. In this paper, we propose a camera-based path planning framework that allows the fast preparation and execution of robot tasks in dynamic environments which leads to less planning overhead, fast program generation and reduced cost and hence overcomes the major impediments for the usage of industrial robots for automation in SMEs with focus on low volume and high variant manufacturing. The framework resolves existing problems in different steps. The exact position and orientation of the workpiece are determined from a 3D environment model scanned by an optical sensor. The so retrieved information is used to plan a collision-free path that meets the boundary conditions of the specific robot task. Experiments show the potential and effectiveness of the the framework presented here by evaluating a case study. KW - Author Keywords: Industrial robot, Automatic robot programming, SME, low volume, high variant, path planning, matching, machine vision KW - IEEE Keywords: Solid modeling, Path planning, Three-dimensional displays, Robot kinematics, Pipelines, Task analysis KW - INSPEC (Controlled Indexing): cameras, collision avoidance, industrial robots, mobile robots, small-to-medium enterprises KW - INSPEC (Non-Controlled Indexing): high variant manufacturing, industrial robots, complex robot tasks, medium-sized enterprises, camera-based path, planning overhead, fast program generation, collision-free path, specific robot task, SME Y1 - 2019 UR - https://ieeexplore.ieee.org/document/8600833 SN - 978-1-5386-7544-1 U6 - http://dx.doi.org/10.1109/M2VIP.2018.8600833 SP - 1 EP - 6 PB - IEEE ER - TY - CHAP A1 - Mertens, K. T1 - „String-Dunkelkennlinien-Technik zur Diagnose von PV-Anlagen“, Solarkampagne des Kreises Steinfurt, Betriebs- und Sicherheitstagung der DGS, Berlin, 17.10.2018 Y1 - 2018 ER - TY - CHAP A1 - Mertens, Konrad T1 - „String-Dunkelkennlinien: Eine neue effiziente Methode zur Anlagenevaluation“, 33. Symposium Photovoltaische Solarenergie, Staffelstein, 27.04.2018 KW - Photovoltaik, Solarstrom Y1 - 2018 ER - TY - CHAP A1 - Mertens, K. T1 - "Do Photovoltaics make sense in countries like Germany?", Invited Paper zur 7th International Energy and Sustainability Confrerence, Cologne Institute for Renewable Energy CIRE der TH Köln, 17.05.2018, Köln Y1 - 2018 ER - TY - CHAP A1 - Mertens, K. A1 - Arnds, A. A1 - Diehl, M. T1 - "Quick and Effective Plant Evaluation Using Dark-IV String Curves" T2 - Proceedings of 33st European Photovoltaic Solar Energy Conference, Amsterdam, 2017 Y1 - 2017 SN - 3-936338-47-7 U6 - http://dx.doi.org/10.4229/EUPVSEC201 SP - 2346 EP - 2348 CY - Amsterdam ER - TY - CHAP A1 - Mertens, K. T1 - „Status der Photovoltaik“, Tagung „Solarstrahlung - Wirkung, Anwendung, Messung und Simulation“, Deutsche Akademie für Photobiologie und Phototechnologie e.V., Freiburg, 19.05.2017 Y1 - 2017 ER - TY - CHAP A1 - Rebel, G. A1 - Estevez, F. A1 - Schulz, I. A1 - Glösekötter, P. T1 - Fast Constant Time Memory Allocator for inter Task Communication in Ultra Low Energy Embedded Systems T2 - 9th Conference on Ph.D. Research in Microelectonics & Electronics N2 - Fast Constant Time Memory Allocator for Inter Task Communication in Ultra Low Energy Embedded Systems Y1 - 2013 SN - 978-1-4673-4580-4 U6 - http://dx.doi.org/10.25974/fhms-708 SP - 149 PB - IEEE ER - TY - CHAP A1 - Estevez, F. A1 - Rebel, G. A1 - González, J. A1 - Palomares, J.M. A1 - Glösekötter, P. T1 - Body energy harvesting for WSN. State of art and examples T2 - Proceedings JCE 09/2013 N2 - Body energy harvesting for WSN. State of art and examples Y1 - 2013 U6 - http://dx.doi.org/10.25974/fhms-707 PB - JCE ER -