TY - CHAP A1 - Atkinson, Colin A1 - Gerbig, Ralph A1 - Barth, Florian A1 - Freiling, Felix A1 - Schinzel, Sebastian A1 - Hadasch, Frank A1 - Maedche, Alexander A1 - Müller, Benjamin T1 - Reducing the Incidence of Unintended, Human-Caused Information Flows in Enterprise Systems T2 - Enterprise Distributed Object Computing Conference Workshops (EDOCW), 2012 IEEE 16th International Y1 - 2012 U6 - http://dx.doi.org/10.1109/EDOCW.2012.12 SP - 11 EP - 18 ET - 3M4SE 2012 ER - TY - CHAP A1 - Aviram, Nimrod A1 - Schinzel, Sebastian A1 - Somorovsky, Juraj A1 - Heninger, Nadia A1 - Dankel, Maik A1 - Steube, Jens A1 - Valenta, Luke A1 - Adrian, David A1 - Halderman, J. Alex A1 - Dukhovni, Viktor A1 - Käsper, Emilia A1 - Cohney, Shaanan A1 - Engels, Susanne A1 - Paar, Christof A1 - Shavitt, Yuval T1 - DROWN: Breaking TLS Using SSLv2 T2 - 25th Usenix Security Symposium Y1 - 2016 SP - 689 EP - 706 PB - Usenix Association. CY - Austin, TX. ER - TY - CHAP A1 - Bauer, Johannes A1 - Schinzel, Sebastian A1 - Felix, C. A1 - Freiling, Andreas T1 - Information leakage behind the curtain: Abusing anti-EMI features for covert communication T2 - Hardware Oriented Security and Trust (HOST), 2016 IEEE International Symposium on Y1 - 2016 U6 - http://dx.doi.org/10.1109/HST.2016.7495570 SP - 130 EP - 134 ER - TY - JOUR A1 - Brinkmann, Marcus A1 - Dresen, Christian A1 - Merget, Robert A1 - Poddebniak, Damian A1 - Müller, Jens A1 - Somorovsky, Juraj A1 - Schwenk, Jörg A1 - Schinzel, Sebastian T1 - ALPACA: Application Layer Protocol Confusion - Analyzing and Mitigating Cracks in TLS Authentication JF - 30th USENIX Security Symposium Y1 - 2021 UR - https://www.usenix.org/conference/usenixsecurity21/presentation/brinkmann 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 - Ebinger, Peter A1 - Schinzel, Sebastian A1 - Schmuckler, Martin T1 - Security mechanisms of a legal peer-to-peer file sharing system T2 - IADIS International Conference Applied Computing Y1 - 2008 ER - TY - CHAP A1 - Freiling, Felix A1 - Schinzel, Sebastian T1 - Detecting Hidden Storage Side Channel Vulnerabilities in Networked Applications T2 - IFIP sec2011 - Future Challenges in Security and Privacy for Academia and Industry Y1 - 2011 SN - 978-3-642-21423-3 U6 - http://dx.doi.org/10.1007/978-3-642-21424-0_4 SP - 41 EP - 55 PB - Springer, Berlin, Heidelberg ET - Volume 354 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 - JOUR A1 - Gierling, Markus A1 - Saatjohann, Christoph A1 - Dresen, Christian A1 - Köbe, Julia A1 - Rath, Benjamin A1 - Eckardt, Lars A1 - Schinzel, Sebastian T1 - Reviewing Cyber Security Research of Implantable Medical Rhythm Devices regarding Patients’ Risk JF - 86. Jahrestagung und Herztage 2020 der DGK N2 - Introduction: The recent publication of several critical cyber security issues in cardiac implantable devices and the resulting press coverage upsets affected users and their trust in medical device producers. Reviewing the published security vulnerabilities regarding networked medical devices, it raises the question, if the reporting media, the responsible security researchers, and the producers handle security vulnerabilities appropriately. Are the media reports of security vulnerabilities in medical devices meaningful in a way that patients can assess their respective risk for an attack via the security vulnerability? The collaboration between IT-security experts and clinicians aims at reviewing published security vulnerabilities of rhythm devices, and evaluate overall patients risks. Methodology: We performed a literature review on security vulnerabilities in implantable medical devices with a focus on cardiac devices. We analyzed (Fig. 1) the (1) requirements for an attacker and the (2) technical feasibility and clustered them in three different scenarios: The first scenario requires that the attacker physically approaches a victim with a programming device. The second scenario requires proximity to the victim, e.g., within a few meters. The third and strongest attacker scenario is a remote attack that doesn’t require any physical proximity to the victim. We then compare the attacker scenarios and (3) the overall patients’ risks with the press coverage (overhyped, adequate, underhyped). (4) The resulting overall patients’ risk was rated by clinicians (security vulnerability of patients’ data, dangerous programming possible). Results: Out of the three analyzed incidents, we found one to be underhyped, one to be overhyped, and one was appropriate compared to the medial coverage (Fig. 2). The most occurring technical issues were based on the absence of basic security primitives. The patient damage for all of the analyzed incidents was fatal in the worst-case scenario. Further, the patient damage and the overall patient risks are disjunct due to the missing capability of performing large scale attacks. Conclusion: The resulting overall patients’ risks may not adequately reflect the patient damage in the considered cases. Often, the overall patient risk is not as severe as the necessary attacker capabilities are high and it would require strongly motivated attackers to perform the attack. Therefore, most of the reviewed cases are considered with a smaller overall patient risk than implied by press reports. Reviewing the ongoing IT-Security trends regarding implantable medical devices shows an increasing focus on researching in the field of medical device security. Therefore, further findings in the near future are to be expected. To deal with this fact in a responsible way, proper proactive knowledge management is mandatory. We recommend medical staff to critically reflect reports in mass media due to possible sensationalism. Therefore, we propose a joint approach in combining the technical expertise of cyber security experts with clinical aspects of medical experts, to ensure a solid understanding of a newly published vulnerability. The combination of both communities promises to result in better predictions for patients’ risks from security vulnerabilities in implanted cardiac devices. KW - Cyber Security KW - Cardiac Implantable Devices Y1 - 2020 U6 - http://dx.doi.org/10.1007/s00392-020-01621-0 VL - Band 109, Supplement 1, April 2020 SP - 1 EP - 2 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 -