T-024-006 Threat Model Document

Executive Summary

This Threat Model Document provides a comprehensive security analysis of the Legit.Health Plus medical device software using the STRIDE methodology. The document identifies potential threats, vulnerabilities, and attack vectors that could compromise the Confidentiality, Integrity, Availability, and Authenticity (CIAA) of the device and its data. This analysis forms the foundation for security risk management activities and guides the implementation of appropriate security controls in accordance with FDA Cybersecurity Guidance, EU NIS2 Directive, and relevant medical device standards.

Key Findings

• Critical Assets Identified: Patient health data, diagnostic algorithms, API endpoints, authentication systems
• Primary Threat Actors: External attackers, malicious insiders, compromised third-party systems
• High-Risk Areas: API authentication, data transmission, SOUP components, integration points
• Security Controls: Multi-layered defense including encryption, authentication, monitoring, and secure development practices

Document Control

Version	Date	Author	Description
1.0	2025-08-29	Technical Team	Initial threat model creation

Regulatory Alignment

This document has been prepared in accordance with:

• FDA Premarket Cybersecurity Guidance (2023)
• FDA Postmarket Management of Cybersecurity in Medical Devices (2016)
• EU Directive 2022/2555 (NIS2) on cybersecurity
• MDCG 2019-16 - Guidance on Cybersecurity for medical devices
• IMDRF/CYBER WG/N60FINAL:2020 - Principles and Practices for Medical Device Cybersecurity
• IEC 62443 series - Industrial communication networks security
• ISO/IEC 27001:2022 - Information security management systems
• NIST Cybersecurity Framework v1.1

Scope and Boundaries

In Scope

• Legit.Health Plus medical device software (all components)
• API endpoints and REST interfaces
• Authentication and authorization mechanisms
• Data storage and transmission
• Third-party integrations (FHIR, HL7)
• AI/ML models and algorithms
• Web and mobile applications
• SOUP components
• Cloud infrastructure (AWS)

Out of Scope

• Physical security of healthcare facilities
• End-user device security (beyond minimum requirements)
• Third-party healthcare information systems (except integration points)
• Network infrastructure of healthcare organizations

System Overview and Architecture

Product Description

Legit.Health Plus is a cloud-based medical device software that provides:

• AI-powered analysis of dermatological images
• Severity assessment using validated clinical scoring systems
• Probabilistic distribution of ICD-10/11 categories
• Clinical decision support for healthcare professionals

System Architecture

The system follows a microservices architecture deployed on AWS cloud infrastructure:

┌─────────────────────────────────────────────────────────────┐
│                    Healthcare Organization                    │
│  ┌──────────────┐  ┌──────────────┐  ┌──────────────┐      │
│  │     HCP      │  │     ITP      │  │   Patient    │      │
│  │  Interface   │  │ Integration  │  │    Portal    │      │
│  └──────┬───────┘  └──────┬───────┘  └──────┬───────┘      │
│         │                  │                  │              │
└─────────┼──────────────────┼──────────────────┼──────────────┘
          │                  │                  │
          ▼                  ▼                  ▼
    ┌─────────────────────────────────────────────────────┐
    │              API Gateway (TLS 1.3)                   │
    │            ┌──────────────────────┐                 │
    │            │   Authentication     │                 │
    │            │   (OAuth 2.0/JWT)    │                 │
    │            └──────────────────────┘                 │
    └─────────────────────────────────────────────────────┘
                            │
    ┌───────────────────────┼────────────────────────────┐
    │                       ▼                             │
    │  ┌──────────────────────────────────────────┐      │
    │  │         Application Services              │      │
    │  │  ┌────────────┐  ┌────────────┐         │      │
    │  │  │  Image     │  │   FHIR     │         │      │
    │  │  │ Processing │  │ Compliance │         │      │
    │  │  └────────────┘  └────────────┘         │      │
    │  └──────────────────────────────────────────┘      │
    │                       │                             │
    │  ┌──────────────────────────────────────────┐      │
    │  │         AI/ML Engine                      │      │
    │  │  ┌────────────┐  ┌────────────┐         │      │
    │  │  │ Diagnostic  │  │  Severity  │         │      │
    │  │  │   Models    │  │  Scoring   │         │      │
    │  │  └────────────┘  └────────────┘         │      │
    │  └──────────────────────────────────────────┘      │
    │                       │                             │
    │  ┌──────────────────────────────────────────┐      │
    │  │         Data Layer                        │      │
    │  │  ┌────────────┐  ┌────────────┐         │      │
    │  │  │  MongoDB    │  │    AWS S3   │         │      │
    │  │  │ (Encrypted) │  │ (Encrypted) │         │      │
    │  │  └────────────┘  └────────────┘         │      │
    │  └──────────────────────────────────────────┘      │
    │                                                      │
    │              AWS Cloud Infrastructure               │
    └──────────────────────────────────────────────────┘

Data Flow Analysis

Primary Data Flows

DF-1: Image Upload and Processing

User Device → API Gateway → Authentication Service → Image Processing Service → AI/ML Engine → Database → Response Generation → User Device

Data Elements: Patient images, metadata, authentication tokens, processing results

DF-2: Integration with Healthcare Systems

Healthcare System → FHIR Endpoint → Authentication → Data Validation → Processing → Response Formatting → Healthcare System

Data Elements: Patient identifiers, clinical data, diagnostic outputs, ICD codes

DF-3: Clinical Decision Support

HCP Interface → API Gateway → Clinical Algorithm → Database Query → Risk Assessment → Decision Support Output → HCP Interface

Data Elements: Clinical parameters, historical data, risk scores, recommendations

Trust Boundaries

TB-1: External Network Boundary

• Location: Between healthcare organization networks and internet
• Controls: Firewall, TLS 1.3, API rate limiting

TB-2: Authentication Boundary

• Location: API Gateway authentication layer
• Controls: OAuth 2.0, JWT tokens, MFA support

TB-3: Data Processing Boundary

• Location: Between application services and AI/ML engine
• Controls: Input validation, sandboxing, output sanitization

TB-4: Storage Boundary

• Location: Database and file storage interfaces
• Controls: Encryption at rest, access controls, audit logging

Threat Identification - STRIDE Analysis

Component: API Gateway

TM-API-001: Spoofing - Unauthorized API Access

• Threat Type: Spoofing
• Description: Attacker impersonates legitimate user to gain API access
• Attack Vector: Stolen credentials, session hijacking, token replay
• CIAA Impact: Confidentiality (High), Integrity (High), Authenticity (High)
• Severity: 5
• Exploitability: 3
• Risk Level: 15 (Not Acceptable)
• Mitigations:
  • Multi-factor authentication (MFA)
  • Token expiration and rotation
  • IP allowlisting for healthcare organizations
  • Anomaly detection for suspicious access patterns

TM-API-002: Tampering - API Request Manipulation

• Threat Type: Tampering
• Description: Attacker modifies API requests in transit
• Attack Vector: Man-in-the-middle attack, proxy manipulation
• CIAA Impact: Integrity (High), Availability (Medium)
• Severity: 4
• Exploitability: 2
• Risk Level: 8 (AFAP)
• Mitigations:
  • TLS 1.3 with certificate pinning
  • Request signing with HMAC
  • Input validation and sanitization

TM-API-003: Repudiation - Audit Log Tampering

• Threat Type: Repudiation
• Description: Attacker attempts to modify or delete audit logs
• Attack Vector: Direct database access, log injection
• CIAA Impact: Integrity (High), Authenticity (High)
• Severity: 3
• Exploitability: 2
• Risk Level: 6 (AFAP)
• Mitigations:
  • Immutable audit logs (write-once storage)
  • Log forwarding to SIEM
  • Digital signatures on log entries

TM-API-004: Information Disclosure - API Enumeration

• Threat Type: Information Disclosure
• Description: Attacker discovers API endpoints and data structures
• Attack Vector: API scanning, error message analysis
• CIAA Impact: Confidentiality (Medium)
• Severity: 2
• Exploitability: 4
• Risk Level: 8 (AFAP)
• Mitigations:
  • Generic error messages
  • API documentation access control
  • Rate limiting on discovery attempts

TM-API-005: Denial of Service - API Flooding

• Threat Type: Denial of Service
• Description: Attacker overwhelms API with requests
• Attack Vector: Distributed attack, resource exhaustion
• CIAA Impact: Availability (High)
• Severity: 4
• Exploitability: 3
• Risk Level: 12 (AFAP)
• Mitigations:
  • Rate limiting per user/IP
  • DDoS protection (AWS Shield)
  • Auto-scaling infrastructure
  • Circuit breaker patterns

TM-API-006: Elevation of Privilege - Authorization Bypass

• Threat Type: Elevation of Privilege
• Description: Attacker gains unauthorized access to privileged functions
• Attack Vector: JWT manipulation, role confusion
• CIAA Impact: Confidentiality (High), Integrity (High), Authenticity (High)
• Severity: 5
• Exploitability: 2
• Risk Level: 10 (AFAP)
• Mitigations:
  • Role-based access control (RBAC)
  • Principle of least privilege
  • Regular permission audits
  • JWT signature verification

Component: AI/ML Engine

TM-ML-001: Spoofing - Model Impersonation

• Threat Type: Spoofing
• Description: Attacker replaces legitimate ML model with malicious version
• Attack Vector: Supply chain attack, insider threat
• CIAA Impact: Integrity (High), Authenticity (High)
• Severity: 5
• Exploitability: 1
• Risk Level: 5 (Acceptable)
• Mitigations:
  • Model signing and verification
  • Secure model storage
  • Version control with integrity checks
  • Deployment pipeline security

TM-ML-002: Tampering - Training Data Poisoning

• Threat Type: Tampering
• Description: Attacker manipulates training data to bias model outputs
• Attack Vector: Data injection, insider manipulation
• CIAA Impact: Integrity (High)
• Severity: 4
• Exploitability: 2
• Risk Level: 8 (AFAP)
• Mitigations:
  • Data validation and sanitization
  • Anomaly detection in training data
  • Model performance monitoring
  • Regular model retraining with verified data

TM-ML-003: Information Disclosure - Model Extraction

• Threat Type: Information Disclosure
• Description: Attacker extracts proprietary model parameters
• Attack Vector: API queries, side-channel attacks
• CIAA Impact: Confidentiality (High)
• Severity: 3
• Exploitability: 2
• Risk Level: 6 (AFAP)
• Mitigations:
  • Rate limiting on predictions
  • Output perturbation
  • Model watermarking
  • Query pattern monitoring

TM-ML-004: Denial of Service - Adversarial Inputs

• Threat Type: Denial of Service
• Description: Attacker submits inputs designed to cause model failure
• Attack Vector: Adversarial examples, edge cases
• CIAA Impact: Availability (Medium), Integrity (Medium)
• Severity: 3
• Exploitability: 3
• Risk Level: 9 (AFAP)
• Mitigations:
  • Input validation and bounds checking
  • Adversarial training
  • Graceful error handling
  • Fallback mechanisms

Component: Data Storage

TM-DS-001: Spoofing - Database Connection Hijacking

• Threat Type: Spoofing
• Description: Attacker impersonates application to access database
• Attack Vector: Connection string theft, credential compromise
• CIAA Impact: Confidentiality (High), Integrity (High)
• Severity: 5
• Exploitability: 2
• Risk Level: 10 (AFAP)
• Mitigations:
  • Encrypted connections (TLS)
  • Certificate-based authentication
  • Database firewall rules
  • Secrets management (AWS Secrets Manager)

TM-DS-002: Tampering - Direct Database Modification

• Threat Type: Tampering
• Description: Attacker modifies patient data directly in database
• Attack Vector: SQL injection, insider access
• CIAA Impact: Integrity (High)
• Severity: 5
• Exploitability: 2
• Risk Level: 10 (AFAP)
• Mitigations:
  • Parameterized queries
  • Database access controls
  • Change detection and alerting
  • Database activity monitoring

TM-DS-003: Information Disclosure - Data Breach

• Threat Type: Information Disclosure
• Description: Attacker gains access to patient health information
• Attack Vector: Database vulnerability, backup exposure
• CIAA Impact: Confidentiality (High)
• Severity: 5
• Exploitability: 2
• Risk Level: 10 (AFAP)
• Mitigations:
  • Encryption at rest (AES-256)
  • Data masking and tokenization
  • Access logging and monitoring
  • Regular security assessments

TM-DS-004: Denial of Service - Storage Exhaustion

• Threat Type: Denial of Service
• Description: Attacker fills storage with excessive data
• Attack Vector: Upload abuse, log flooding
• CIAA Impact: Availability (High)
• Severity: 3
• Exploitability: 3
• Risk Level: 9 (AFAP)
• Mitigations:
  • Storage quotas per tenant
  • Data retention policies
  • Monitoring and alerting
  • Auto-scaling storage

Component: Integration Layer (FHIR/HL7)

TM-INT-001: Spoofing - Healthcare System Impersonation

• Threat Type: Spoofing
• Description: Attacker pretends to be legitimate healthcare system
• Attack Vector: Certificate forgery, DNS hijacking
• CIAA Impact: Confidentiality (High), Authenticity (High)
• Severity: 4
• Exploitability: 2
• Risk Level: 8 (AFAP)
• Mitigations:
  • Mutual TLS authentication
  • Certificate validation
  • DNS security (DNSSEC)
  • Integration allowlisting

TM-INT-002: Tampering - Message Modification

• Threat Type: Tampering
• Description: Attacker modifies FHIR/HL7 messages in transit
• Attack Vector: Man-in-the-middle, proxy manipulation
• CIAA Impact: Integrity (High)
• Severity: 4
• Exploitability: 2
• Risk Level: 8 (AFAP)
• Mitigations:
  • Message signing (digital signatures)
  • End-to-end encryption
  • Message integrity checks
  • Sequence number validation

TM-INT-003: Information Disclosure - Metadata Leakage

• Threat Type: Information Disclosure
• Description: Integration metadata reveals sensitive information
• Attack Vector: Traffic analysis, header inspection
• CIAA Impact: Confidentiality (Medium)
• Severity: 3
• Exploitability: 3
• Risk Level: 9 (AFAP)
• Mitigations:
  • Metadata minimization
  • Traffic padding
  • VPN tunneling for integrations
  • Header sanitization

Component: Authentication System

TM-AUTH-001: Spoofing - Credential Theft

• Threat Type: Spoofing
• Description: Attacker steals user credentials
• Attack Vector: Phishing, keylogging, credential stuffing
• CIAA Impact: Confidentiality (High), Authenticity (High)
• Severity: 5
• Exploitability: 3
• Risk Level: 15 (Not Acceptable)
• Mitigations:
  • Multi-factor authentication (MFA)
  • Password complexity requirements
  • Account lockout policies
  • Breach detection services

TM-AUTH-002: Tampering - Session Hijacking

• Threat Type: Tampering
• Description: Attacker takes over authenticated session
• Attack Vector: Session fixation, XSS, token theft
• CIAA Impact: Integrity (High), Authenticity (High)
• Severity: 4
• Exploitability: 3
• Risk Level: 12 (AFAP)
• Mitigations:
  • Secure session management
  • HTTPOnly and Secure cookies
  • Session timeout policies
  • Device fingerprinting

TM-AUTH-003: Elevation of Privilege - Privilege Escalation

• Threat Type: Elevation of Privilege
• Description: User gains unauthorized elevated permissions
• Attack Vector: Role manipulation, authorization bugs
• CIAA Impact: Confidentiality (High), Integrity (High)
• Severity: 5
• Exploitability: 2
• Risk Level: 10 (AFAP)
• Mitigations:
  • Principle of least privilege
  • Regular permission reviews
  • Role-based access control (RBAC)
  • Separation of duties

Component: Third-Party Libraries (SOUP)

TM-SOUP-001: Tampering - Supply Chain Attack

• Threat Type: Tampering
• Description: Compromised third-party component introduces vulnerability
• Attack Vector: Dependency confusion, typosquatting
• CIAA Impact: Integrity (High), Confidentiality (High)
• Severity: 5
• Exploitability: 2
• Risk Level: 10 (AFAP)
• Mitigations:
  • Software Bill of Materials (SBOM)
  • Dependency scanning (Trivy)
  • Package signing verification
  • Private package repositories

TM-SOUP-002: Information Disclosure - Known Vulnerabilities

• Threat Type: Information Disclosure
• Description: Unpatched vulnerabilities in SOUP components
• Attack Vector: CVE exploitation, zero-day attacks
• CIAA Impact: Confidentiality (High), Integrity (High), Availability (High)
• Severity: 4
• Exploitability: 3
• Risk Level: 12 (AFAP)
• Mitigations:
  • Regular vulnerability scanning
  • Automated patch management
  • Security advisory monitoring
  • Component isolation

Threat Actors

External Attackers

TA-1: Cybercriminals

• Motivation: Financial gain through ransomware or data theft
• Capability: Medium to High
• Resources: Moderate
• Risk Tolerance: High
• Primary Targets: Patient data, system availability

TA-2: Nation-State Actors

• Motivation: Espionage, disruption of healthcare services
• Capability: Very High
• Resources: Extensive
• Risk Tolerance: Low
• Primary Targets: Intellectual property, critical infrastructure

TA-3: Hacktivists

• Motivation: Ideological, publicity
• Capability: Low to Medium
• Resources: Limited
• Risk Tolerance: High
• Primary Targets: System availability, reputation damage

Internal Threats

TA-4: Malicious Insiders

• Motivation: Financial gain, revenge
• Capability: High (privileged access)
• Resources: Internal knowledge
• Risk Tolerance: Variable
• Primary Targets: Patient data, system integrity

TA-5: Negligent Users

• Motivation: None (unintentional)
• Capability: Low
• Resources: Legitimate access
• Risk Tolerance: N/A
• Primary Targets: Data confidentiality (accidental disclosure)

Third-Party Threats

TA-6: Compromised Partners

• Motivation: Variable (depends on attacker)
• Capability: Medium
• Resources: Integration access
• Risk Tolerance: Variable
• Primary Targets: Integration points, data exchange

Attack Vectors

AV-1: Network-Based Attacks

• API exploitation
• Man-in-the-middle attacks
• DDoS attacks
• Network scanning and enumeration

AV-2: Application-Layer Attacks

• Injection attacks (SQL, NoSQL, Command)
• Cross-site scripting (XSS)
• Cross-site request forgery (CSRF)
• Business logic exploitation

AV-3: Authentication and Authorization Attacks

• Credential stuffing
• Password spraying
• Token manipulation
• Session hijacking

AV-4: Data-Focused Attacks

• Data exfiltration
• Data manipulation
• Ransomware
• Database exploitation

AV-5: Supply Chain Attacks

• Compromised dependencies
• Malicious packages
• Build pipeline compromise
• Third-party service compromise

AV-6: Physical and Environmental

• Device theft
• Unauthorized physical access
• Environmental failures
• Natural disasters

Security Controls Mapping

Preventive Controls

Control ID	Control Description	Threat IDs Addressed	Standard Reference
PC-001	Multi-factor authentication	TM-API-001, TM-AUTH-001	NIST SP 800-63B
PC-002	End-to-end encryption (TLS 1.3)	TM-API-002, TM-INT-002	NIST SP 800-52
PC-003	Input validation and sanitization	TM-API-002, TM-ML-004	OWASP Top 10
PC-004	Role-based access control	TM-API-006, TM-AUTH-003	ISO 27001:A.9.2
PC-005	Secure coding practices	TM-DS-002, TM-SOUP-001	ISO 27001:A.14.2
PC-006	API rate limiting	TM-API-005, TM-ML-003	NIST CSF PR.PT-5
PC-007	Database encryption at rest	TM-DS-003	ISO 27001:A.10.1
PC-008	Secure session management	TM-AUTH-002	OWASP ASVS 3.0
PC-009	Package integrity verification	TM-SOUP-001	NIST CSF PR.DS-6
PC-010	Network segmentation	TM-DS-001, TM-INT-001	IEC 62443-3-3

Detective Controls

Control ID	Control Description	Threat IDs Addressed	Standard Reference
DC-001	Security information and event management (SIEM)	All threats	ISO 27001:A.12.4
DC-002	Intrusion detection system (IDS)	TM-API-001, TM-DS-001	NIST CSF DE.CM-1
DC-003	Database activity monitoring	TM-DS-002, TM-DS-003	ISO 27001:A.12.4
DC-004	Anomaly detection in API usage	TM-API-001, TM-API-004	NIST CSF DE.AE-1
DC-005	File integrity monitoring	TM-ML-001, TM-DS-002	IEC 62443-3-3:SR 3.4
DC-006	Vulnerability scanning	TM-SOUP-002	ISO 27001:A.12.6
DC-007	Performance monitoring	TM-API-005, TM-ML-004	NIST CSF DE.CM-7
DC-008	Audit log review	TM-API-003	ISO 27001:A.12.4

Corrective Controls

Control ID	Control Description	Threat IDs Addressed	Standard Reference
CC-001	Incident response plan	All threats	ISO 27001:A.16.1
CC-002	Automated failover	TM-API-005, TM-DS-004	NIST CSF RS.MI-1
CC-003	Data backup and recovery	TM-DS-002, TM-DS-003	ISO 27001:A.12.3
CC-004	Patch management process	TM-SOUP-002	IEC 62443-2-1
CC-005	Security orchestration and automated response (SOAR)	Multiple	NIST CSF RS.AN-5

Risk Assessment Methodology

Risk Calculation Formula

Risk Score = Severity × Exploitability

Severity Ratings

Level	Description	Impact
5	Catastrophic	Death or permanent impairment
4	Critical	Serious injury or temporary impairment
3	Serious	Moderate injury requiring medical intervention
2	Minor	Minor injury or temporary discomfort
1	Negligible	No injury or slight inconvenience

Exploitability Ratings

Level	Description	Likelihood
5	Very High	Easily exploitable, automated tools available
4	High	Exploitable with moderate effort
3	Medium	Requires specific conditions or knowledge
2	Low	Difficult to exploit, requires significant resources
1	Very Low	Theoretical, requires exceptional circumstances

Risk Acceptability Matrix

Risk Score	Classification	Action Required
0-5	Acceptable	Monitor and maintain controls
6-12	AFAP (As Far As Possible)	Implement additional controls where feasible
13-25	Not Acceptable	Mandatory risk reduction required

Mitigations and Countermeasures

Defense in Depth Strategy

The security architecture implements multiple layers of defense:

1. Perimeter Security

   • Web Application Firewall (WAF)
   • DDoS protection (AWS Shield)
   • Geographic IP filtering

2. Network Security

   • Network segmentation
   • Virtual Private Cloud (VPC)
   • Security groups and NACLs

3. Application Security

   • Secure coding practices
   • Regular security testing
   • Dependency management

4. Data Security

   • Encryption in transit and at rest
   • Data loss prevention (DLP)
   • Backup and recovery

5. Identity and Access Management

   • Multi-factor authentication
   • Principle of least privilege
   • Regular access reviews

Critical Security Requirements

CSR-001: Secure Communication

All communication between components shall use TLS 1.3 or higher with strong cipher suites.

CSR-002: Authentication Strength

All user authentication shall require multi-factor authentication for privileged accounts.

CSR-003: Data Protection

All patient health information shall be encrypted using AES-256 at rest and in transit.

CSR-004: Audit Logging

All security-relevant events shall be logged with tamper-resistant mechanisms.

CSR-005: Vulnerability Management

All components shall undergo regular vulnerability assessments with critical patches applied within 30 days.

CSR-006: Access Control

All access to patient data shall be based on the principle of least privilege with role-based controls.

CSR-007: Incident Response

A documented incident response plan shall be maintained and tested annually.

CSR-008: Third-Party Security

All third-party components shall be assessed for security vulnerabilities before integration.

Threat Model Maintenance

Update Triggers

The threat model shall be updated when:

• Major architectural changes occur
• New features or integrations are added
• Significant vulnerabilities are discovered
• Regulatory requirements change
• Annual review cycle

Review Process

1. Quarterly threat intelligence review
2. Semi-annual architecture review
3. Annual comprehensive threat model update
4. Ad-hoc updates for critical changes

References to Related Documents

Internal Documents

• R-TF-013-002: Risk Management File
• R-TF-024-004: Security Risk Assessment Report
• T-012-029: Software Architecture Description
• GP-013: Information Security and Cybersecurity Procedure
• R-TF-001-006: Instructions for Use (IFU)
• R-TF-007-002: Post-Market Surveillance Plan

External Standards and Guidance

• FDA Premarket Cybersecurity Guidance (2023)
• FDA Postmarket Management of Cybersecurity in Medical Devices (2016)
• MDCG 2019-16 - Guidance on Cybersecurity for medical devices
• IMDRF/CYBER WG/N60FINAL:2020
• IEC 62443 series
• ISO/IEC 27001:2022
• NIST Cybersecurity Framework v1.1
• OWASP Top 10 (2021)
• STRIDE Threat Modeling Methodology

Appendices

Appendix A: Threat ID Mapping to Risk Management

Threat Model ID	Risk Management ID	Description
TM-API-001	R-3YJ	Unauthorized access and data breach
TM-API-002	R-HH0	Data tampering
TM-API-005	R-2TP	Service availability issues
TM-AUTH-001	R-D1I	Unauthorized patient access
TM-INT-001	R-U6M	System incompatibility
TM-INT-002	R-A96	Classification system mismatch
TM-ML-002	R-SKK	Incorrect results shown
TM-SOUP-001	R-9SS	SOUP vulnerabilities
TM-SOUP-002	R-MQ1	Unpatched SOUP components

Appendix B: CIAA Property Definitions

• Confidentiality: Protection of information from unauthorized disclosure
• Integrity: Protection of information from unauthorized modification
• Availability: Ensuring authorized users have reliable and timely access
• Authenticity: Verification that data, transactions, and communications are genuine

Appendix C: Acronyms and Abbreviations

• API: Application Programming Interface
• CIAA: Confidentiality, Integrity, Availability, Authenticity
• CVE: Common Vulnerabilities and Exposures
• DDoS: Distributed Denial of Service
• FHIR: Fast Healthcare Interoperability Resources
• HCP: Healthcare Professional
• HL7: Health Level Seven
• ICD: International Classification of Diseases
• ITP: IT Professional
• JWT: JSON Web Token
• MFA: Multi-Factor Authentication
• RBAC: Role-Based Access Control
• SIEM: Security Information and Event Management
• SOUP: Software of Unknown Provenance
• STRIDE: Spoofing, Tampering, Repudiation, Information Disclosure, Denial of Service, Elevation of Privilege
• TLS: Transport Layer Security

Document Approval

This Threat Model Document has been reviewed and approved by:

Role	Name	Date	Signature
Technical Director	[Name]	[Date]	[Signature]
Quality Manager	[Name]	[Date]	[Signature]
Regulatory Affairs	[Name]	[Date]	[Signature]

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