Christoph Saatjohann

dblp:271/4882 · DBLP profile ↗
← Back
7ranked-venue papers
1as first author
6since 2021 · last 2026
—ORCID · none

Domains — the database's venue-derived domains; a paper can count in several

Security and privacy · 7 · 1 first-author · 6 since 2021
YearPublicationVenuePosition
2026 Measuring Healthcare Data Leaks and Security Flaws at Internet Scale
abstract
Systems that process medical data should be meticulously secured. Yet, network services in healthcare environments often fail to implement basic security measures. For example, previous studies showed that network segmentation flaws led to DICOM systems leaking millions of patient records. In addition to DICOM, healthcare facilities rely heavily on the HL7 and FHIR protocols to transmit data. For nine months, we operated a low-interaction honeypot for medical protocols. We found it was regularly scanned for DICOM but never for HL7 or FHIR, indicating that despite their widespread use and importance for patient data security, the security of these services remains underexplored. In this paper, we present the first large-scale study on HL7 and FHIR services and expand previous work on DICOM. Our large-scale Internet scans, covering the three major healthcare protocols across IPv4 and IPv6 address spaces, identify healthcare systems and uncover data leaks due to authentication flaws. Additionally, we scanned for deficiencies in TLS configurations of these services and known insecure healthcare software. In total, we found 2,841 healthcare services with authentication flaws. 94.4% of all exposed systems do not support transport encryption, and 1,373 systems have known software vulnerabilities, including those with potential for system takeover and CVSS scores up to 9.8. Overall, our study reveals an alarming state of cybersecurity in healthcare deployments, for which we discuss potential reasons and countermeasures. Finally, we report on the coordinated disclosure campaign we initiated to improve the security of patient data.
Nico Brüggemann, Lukas Schmidt, Marvin Dölzer, Marius Brockhoff, Fabian Ising, Christoph Saatjohann, Sebastian Schinzel
EuroS&P6
2025 S/MINE: Collecting and Analyzing S/MIME Certificates at Scale
Gurur Öndarö, Jonas Kaspereit, Samson Umezulike, Christoph Saatjohann, Fabian Ising, Sebastian Schinzel
USENIX Security Symposium4
2024 LanDscAPe: Exploring LDAP weaknesses and data leaks at Internet scale
Jonas Kaspereit, Gurur Öndarö, Gustavo Luvizotto Cesar, Simon Ebbers, Fabian Ising, Christoph Saatjohann, Mattijs Jonker, Ralph Holz, Sebastian Schinzel
USENIX Security Symposium6
2023 Content-Type: multipart/oracle - Tapping into Format Oracles in Email End-to-End Encryption
Fabian Ising, Damian Poddebniak, Tobias Kappert, Christoph Saatjohann, Sebastian Schinzel
USENIX Security Symposium4
2021 Grand Theft App: Digital Forensics of Vehicle Assistant Apps
abstract
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.
Simon Ebbers, Fabian Ising, Christoph Saatjohann, Sebastian Schinzel
ARES3
2021 Listen to Your Heart: Evaluation of the Cardiologic Ecosystem
abstract
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.
Endres Puschner, Christoph Saatjohann, Markus Willing, Christian Dresen, Julia Köbe, Benjamin Rath, Christof Paar, Lars Eckardt, Uwe Haverkamp, Sebastian Schinzel
ARES2
2020 STALK: security analysis of smartwatches for kids
abstract
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.
Christoph Saatjohann, Fabian Ising, Luise Krings, Sebastian Schinzel
ARES1