Updated April 14, 2025
As medical devices become more interconnected, cybersecurity risks in healthcare continue to rise. Ensuring patient safety and data security is now a critical component of FDA approval and regulatory compliance. To protect medical devices from cyber threats, professionals use threat trees and attack trees—powerful tools for identifying vulnerabilities and assessing risks.
In this post, we’ll explore the key differences and similarities between threat trees and attack trees, how they apply to medical device cybersecurity, and their role in the FDA approval process.
Understanding Threat Trees and Attack Trees in Medical Device Cybersecurity
Cybersecurity risk assessment is crucial to medical device safety and FDA approval processes. Two essential tools in threat modeling—threat trees and attack trees—help identify and mitigate security vulnerabilities. While they are closely related, they serve different purposes in cyber risk analysis.
Threat Trees vs. Attack Trees: Definitions & Examples
Threat Trees: Identifying System Vulnerabilities
A threat tree is a structured representation of potential threats and vulnerabilities within a system. It helps identify weak points that adversaries could exploit, enabling proactive risk mitigation.
📌 Example: In medical device cybersecurity, a threat tree might highlight risks such as weak encryption, unauthenticated access, or physical tampering, all of which could compromise patient data or device functionality.
Attack Trees: Mapping the Steps of an Attack
An attack tree is a graphical diagram that models how an adversary could exploit vulnerabilities in a system, detailing the steps, dependencies, and possible outcomes of an attack.
📌 Example: An attack tree for a wireless pacemaker might outline how an attacker could:
1️⃣ Intercept wireless signals between the device and a monitoring system
2️⃣ Exploit authentication weaknesses to gain unauthorized access
3️⃣ Manipulate device settings, potentially endangering the patient’s life
Key Differences and Similarities Between Threat Trees and Attack Trees
✔ Threat Trees: Broad Risk Assessment
- Focus on identifying vulnerabilities within a system
- Provide a high-level view of potential risks
- Help organizations prioritize security measures
✔ Attack Trees: Detailed Attack Scenarios
- Focus on how an attacker could exploit vulnerabilities
- Offer a step-by-step breakdown of potential attacks
- Aid cybersecurity experts in penetration testing and threat mitigation
📌 Example in FDA Approval & Cybersecurity
- Threat Trees: Used in FDA submissions to assess device safety, focusing on potential patient risks and system weaknesses.
- Attack Trees: Used in cybersecurity testing, offering a blueprint for penetration testing and risk mitigation strategies.
How Threat Trees and Attack Trees Work Together
An attack tree can encompass a threat tree within its structure. In cyber risk modeling, the threat tree identifies system vulnerabilities, while the attack tree maps out how those vulnerabilities could be exploited.
✔ Threat Tree → Identifies risks (e.g., weak authentication on a medical device)
✔ Attack Tree → Details attack methods (e.g., steps a hacker could take to bypass authentication)
By combining both approaches, security teams can develop stronger defenses, enhance compliance, and reduce cybersecurity risks.
Conclusion: Strengthening Medical Device Security
Both threat trees and attack trees are essential for ensuring the safety and security of medical devices. By incorporating these tools into cyber risk management, manufacturers, healthcare providers, and regulatory agencies can proactively protect patient safety, device integrity, and sensitive data.
Do you need expert guidance in medical device security and FDA compliance?
Contact us today to ensure your devices meet the highest cybersecurity standards.
Medical Device Attack and Threat Tree FAQs
An attack tree is a visual, hierarchical diagram that maps out the different ways an attacker might compromise a medical device. The goal or consequence (e.g., “unauthorized insulin delivery”) is the root, and potential attack paths branch out from it, showing how an attacker might reach that objective.
While the terms are sometimes used interchangeably, a threat tree focuses more broadly on threat sources and conditions that could impact the device. An attack tree is more tactical and outlines specific steps an attacker might take to exploit a vulnerability.
Attack trees help identify vulnerabilities, prioritize mitigation strategies, and support compliance with FDA cybersecurity guidance. They provide a structured approach to understanding how a device can be compromised and what security controls are needed.
While not explicitly mandated, the FDA strongly encourages structured threat modeling, which may include attack trees, to demonstrate proactive risk identification and mitigation in premarket submissions.
Attack trees can represent both physical and cyber threats, including:
Unauthorized access to wireless communication
Firmware modification
Bypass of authentication
Exploitation of third-party components
Common tools include:
Generic diagram tools like Lucidchart, Draw.io, or Visio
Example: For a Bluetooth-connected insulin pump:
Root Goal: Deliver incorrect insulin dosage
Sub-branch: Intercept Bluetooth communication
Leaf: Use packet sniffer to capture data
Leaf: Replay command to device without authentication
FDA reviewers expect clear, actionable detail—but not exhaustive complexity. Include realistic attack paths, threat actors, and mitigations. Focus on high-impact branches aligned with your device’s critical functions.
Attack trees help correlate specific threats with device vulnerabilities and controls. They complement risk assessments by showing how threats can escalate and which mitigations effectively break the attack path.
Blue Goat Cyber helps manufacturers:
Conduct structured threat modeling with attack trees
Map vulnerabilities to SBOM components
Align threat models with FDA cybersecurity guidance
Identify gaps in security architecture and mitigation plans
Our process supports submission readiness and postmarket risk management.
