Threat Modeling Is Part Science, Part Art. Medical Devices Need Both.
The Challenge: Knowing Where to Look Is the Hard Part
Medical device manufacturers are accustomed to asking what could go wrong. Safety engineering has long depended on that discipline. Cybersecurity introduces a different question: how might a capable adversary deliberately make something go wrong, including through interactions that the design team never intended?
That question becomes difficult when a device is part of a larger system. A home-use product may communicate through a mobile or desktop application, a cellular connection, a cloud service, and local maintenance interfaces. Each component may be defensible on its own, yet the connections between them can introduce vulnerabilities that are easy to miss when teams assess components separately.
Threat modeling is a specialized skill, and relatively few medical device professionals have received substantial hands-on training in it. The work is part science, because it relies on repeatable methods, architecture analysis, and systematic threat identification. It is also part art, because recognizing a realistic attack path demands curiosity, experience, and an ability to challenge assumptions about how people, software, and connected systems behave.
A checklist can remind a team to examine an interface. It cannot, by itself, determine whether an attacker could use that interface to cross a trust boundary, compromise a critical asset, interfere with an update, or create a patient safety concern. That requires informed analysis of the actual device architecture and intended environment of use.
The Solution: Make the Architecture Tell the Story
MedSec approaches threat modeling as a collaborative examination of the medical device system in its current, as-designed state. Its consultants work with manufacturer subject matter experts and review the underlying hardware and software architecture, communications protocols, cryptographic design, existing security controls, and relevant safety information. This creates a grounded picture of what must be protected and where threats could arise.
The engagement develops architecture views that expose different dimensions of risk. A global system view captures critical assets, external data flows, interfaces, and security controls. Additional views examine updatability and patchability, potential multi-patient harm, and security-relevant use cases. Together, these views help prevent important workflows and lifecycle activities from disappearing into a single high-level diagram.
MedSec then applies STRIDE-per-element analysis to the architecture views. The method systematically examines categories of threats, including spoofing, tampering, repudiation, information disclosure, denial of service, and elevation of privilege. The objective is to identify feasible threat events and design weaknesses, document the assumptions behind the analysis, and propose potential mitigations that the manufacturer can evaluate through its cybersecurity risk management process.
The analysis also considers threats associated with manufacturing, supply chain, deployment, interoperability, maintenance, updates, and decommissioning. Those lifecycle pathways matter because a device can inherit exposure from activities that happen well beyond its primary clinical function.
What Manufacturers Gain: Decisions They Can Act On
A useful threat model gives engineers and security leaders more than a catalog of hypothetical attacks. It helps them understand which assets and trust boundaries deserve attention, where existing controls may be insufficient, and which design decisions warrant another look. When completed early enough, this insight can guide mitigations before changes become expensive or disruptive.
MedSec’s deliverable brings the analysis into one structured Threat Model Report, including the scope and methodology, system description, critical assets and controls, architecture views, and feasible threat events with potential mitigations. The manufacturer can use these findings to inform pre- and post-mitigation cybersecurity risk assessments and connect the work to its broader security documentation.
There is a regulatory benefit as well. FDA’s February 2026 guidance, Cybersecurity in Medical Devices: Quality System Considerations and Content of Premarket Submissions, describes expectations relevant to cybersecurity documentation. A well-developed threat model can help manufacturers explain how they examined their system and considered threats during design. It does not replace the manufacturer’s risk management responsibilities, but it provides a more defensible technical basis for them.
The MedSec Difference: Methodology Backed by Medical Device Judgment
Many security practitioners know STRIDE. Fewer are accustomed to applying it to systems where clinical workflows, update mechanisms, multi-patient exposure, embedded components, and regulatory submissions intersect. MedSec focuses on cybersecurity in medical devices and healthcare, bringing that context directly into its threat modeling engagements.
Our approach is deliberately collaborative. The Manufacturer engineers know the product and its design constraints; MedSec brings a structured security perspective and the experience to question assumptions, trace attack paths across interfaces, and translate findings into usable threat events. This helps produce a model that reflects the actual system rather than a generic inventory of security concerns.
The emphasis on distinct architecture views is another practical advantage. Looking separately at global architecture, patchability, multi-patient harm, and security use cases encourages examination of scenarios that might otherwise be overlooked. The resulting report is organized for downstream engineering and cybersecurity risk management work, with clear ownership remaining with the manufacturer for risk decisions, traceability, and ongoing model maintenance.
The Outcome: Better Questions, Earlier Answers
The strongest evidence of a valuable threat modeling exercise is what the team can do with its findings. Can engineers explain the attack paths that matter? Can they identify the controls intended to interrupt those paths? Can they show how the analysis informs cybersecurity risk decisions and design improvements? Those are the questions a mature threat model helps answer.
For manufacturers, the opportunity is to uncover weaknesses while there is still room to act, strengthen the rationale behind security controls, and enter regulatory review with a clearer account of the system’s threat landscape. MedSec helps teams do that work with the technical discipline and judgment that effective medical device threat modeling requires.
Comments