DREAD vs STRIDE vs PASTA Threat Modeling for Medical Devices: Which Should You Use?

If you want a good starting reference for STRIDE, Microsoft’s overview is a solid baseline:
Microsoft: STRIDE threat modeling overview.

Quick Definitions

• STRIDE (Spoofing, Tampering, Repudiation, Information Disclosure, Denial of Service, Elevation of Privilege) is a structured way to identify threat categories across a system design.
• DREAD (Damage, Reproducibility, Exploitability, Affected Users, Discoverability) is a historical scoring model used to prioritize risk using a set of factors.
• PASTA (Process for Attack Simulation and Threat Analysis) is a risk-centric framework that emphasizes attack simulation and traceability from objectives to threats and mitigations.

Why STRIDE Is Often Preferred in Medical Device Cybersecurity

STRIDE tends to be the best “default” for medical device teams because it:

• scales across ecosystems (device, mobile app, cloud, portal, gateway, remote support, service tooling)
• pairs well with data flow diagrams and trust boundary mapping
• provides consistent coverage so teams don’t miss entire categories of threats
• is teachable to cross-functional teams (engineering, QA, RA/QA, IT/OT, product)

The key is to avoid stopping at labels. STRIDE becomes truly effective for MedTech when you translate each threat into:

• abuse cases (what an attacker would try to do), then
• security requirements (what must be true to prevent it), then
• verification evidence (how you prove it works).

For teams looking for practical threat modeling resources and templates, OWASP has a good hub:
OWASP: Threat Modeling.

What Medical Device Teams Actually Need From Threat Modeling

No matter which framework you pick, “good” threat modeling in MedTech usually means you can answer:

• What are the trust boundaries across the device ecosystem?
• What are the highest-risk abuse cases for safety, effectiveness, confidentiality, integrity, and availability?
• What controls reduce those risks?
• What tests and evidence prove the controls are implemented and effective?
• What’s the postmarket plan for monitoring, vulnerability intake, and remediation?

Threat modeling also supports secure development expectations. A helpful reference here is the
NIST SP 800-218 Secure Software Development Framework (SSDF),
which provides a practical structure for secure-by-design practices and evidence.

STRIDE for Medical Devices

Where STRIDE shines

• Design-phase clarity: STRIDE works cleanly with architecture diagrams and data flow diagrams.
• Coverage: It helps teams avoid missing threat categories.
• Repeatability: It’s easy to apply consistently across products and releases.

Where STRIDE needs help

• Prioritization: STRIDE identifies threats, but it doesn’t rank them by impact or urgency.
• Execution: without conversion to requirements and tests, STRIDE can become a “list exercise.”

Best MedTech use: Run STRIDE at each trust boundary and interface (pairing, authentication, updates, APIs, remote support, service mode, configuration changes). Capture outputs as abuse-case statements, not just STRIDE categories.

DREAD for Medical Devices

DREAD is most helpful as a lightweight discussion tool for prioritization—especially when you’re trying to sort a backlog. However, it can be subjective and may not naturally account for clinical impact or patient safety context unless you adapt it.

Best MedTech use: If you use DREAD, adjust it. Add explicit factors for patient safety/clinical impact, detectability, and response capability. Use it to drive decisions, not to win debates about scoring.

If your team wants a standard approach for vulnerability severity scoring (separate from threat modeling), CVSS is widely used:
FIRST: Common Vulnerability Scoring System (CVSS).

PASTA for Medical Devices

PASTA is strong when you need end-to-end realism and traceability—especially for complex systems (device + cloud + mobile + portal + service workflows). The tradeoff is overhead: PASTA can be heavier than many teams need for every product iteration.

Best MedTech use: Use PASTA concepts—especially attack simulation—to enhance a STRIDE baseline. Reserve full PASTA for higher-risk products or complex ecosystems where deep traceability is required.

Which Is Most Effective for Medical Device Cybersecurity?

For most medical device teams, the most effective and sustainable approach is:

• STRIDE as the preferred baseline for consistent coverage and repeatability.
• PASTA-style attack paths to keep the model realistic across the entire ecosystem.
• Lightweight prioritization (DREAD-like or custom) to drive execution and remediation planning.

Recommended STRIDE-First Workflow for MedTech Teams

1. Define the system: device, app, cloud, portal, gateway, remote support, service tooling, manufacturing/test.
2. Map trust boundaries: identify where trust changes and where untrusted input enters.
3. Run STRIDE per boundary: capture threats as abuse cases with attacker goals.
4. Simulate 5–10 attack paths: chain realistic steps across components (PASTA-style thinking).
5. Convert to testable requirements: authentication, authorization, integrity, logging, segmentation, update security.
6. Prioritize: rank by safety impact + likelihood + detectability + feasibility of remediation.
7. Verify and trace: map abuse cases → requirements → test cases → results.
8. Operationalize postmarket: monitoring, vulnerability intake, patch workflow, coordinated disclosure.

Medical Device Threat Modeling Checklist

• We have a clear architecture and data flow view of the entire device ecosystem.
• Trust boundaries are documented and reviewed as the design changes.
• Threats are documented as abuse cases (not just STRIDE labels).
• Each high-risk abuse case maps to testable security requirements.
• Verification evidence exists (tests/results) tied to those requirements.
• Postmarket processes exist for monitoring, vulnerability intake, and patching.

FAQs

Is STRIDE the preferred method for medical device threat modeling?

Often, yes. STRIDE is commonly preferred as a baseline because it is structured, repeatable, and maps well to architecture and data flow diagrams.

Should we still use DREAD?

DREAD can help with prioritization discussions, but it is subjective and often needs adaptation for MedTech, especially to include patient safety and clinical impact.

When should we use PASTA?

Use PASTA concepts (attack simulation) to enhance STRIDE for realism. Consider full PASTA for complex ecosystems or higher-risk products where traceability is critical.

External References (Trusted Resources)

• Microsoft: STRIDE threat modeling overview
• OWASP: Threat Modeling
• NIST SP 800-218: Secure Software Development Framework (SSDF)
• NISTIR 8259A: IoT Device Cybersecurity Capability Core Baseline
• MITRE: CWE Top 25 Most Dangerous Software Weaknesses
• FIRST: Common Vulnerability Scoring System (CVSS)

How Blue Goat Cyber Helps

Blue Goat Cyber helps medical device teams build STRIDE-first threat models that lead to real outcomes: security requirements, verification evidence, and postmarket readiness across the full device ecosystem.

• Medical Device Threat Modeling
• Medical Device Vulnerability & Penetration Testing
• Premarket Cybersecurity Services
• Postmarket Cybersecurity Management
• Contact Blue Goat Cyber

Bottom line: STRIDE is generally the preferred baseline for medical device threat modeling. The most effective MedTech programs add realistic attack paths and a practical prioritization step—then prove controls with verification evidence.