Threat Modeling

Identify and mitigate security threats during system design.

STRIDE Methodology

Process

steps:
  1_scope:
    - Define system boundaries
    - Identify assets
    - Document data flows
    
  2_diagram:
    - Create data flow diagrams
    - Identify trust boundaries
    - Mark entry points
    
  3_identify:
    - Apply STRIDE to each component
    - List potential threats
    - Document attack vectors
    
  4_assess:
    - Rate likelihood and impact
    - Prioritize by risk score
    
  5_mitigate:
    - Design countermeasures
    - Accept/transfer risks
    - Document decisions

Data Flow Diagram

[External User] --> |HTTPS| --> [Load Balancer]
                                      |
                                      v
                               [Web Server]
                                      |
                              [Trust Boundary]
                                      |
                                      v
                                [App Server] --> [Database]

Threat Cards

threat:
  id: T001
  name: SQL Injection
  category: Tampering
  component: Database queries
  likelihood: High
  impact: Critical
  mitigations:
    - Parameterized queries
    - Input validation
    - WAF rules
  status: Mitigated

Best Practices

• Integrate into SDLC
• Review on architecture changes
• Include development team
• Document all decisions
• Regular reassessment

Related Skills

• sast-scanning - Code analysis
• penetration-testing - Validation