Overview
STRIDE and PASTA threat modeling tool with data flow diagram (DFD) builder. Risk assessment matrix, threat tree generation, control recommendations, and architecture review templates for security-by-design validation.
Environment & Scope
Lab Setup
Python 3.9+ | Flask | D3.js for visualization | 2GB RAM
Scope
- • DFD creation (entities, processes, data stores, flows) • STRIDE threat identification per element • Risk scoring (likelihood × impact) • Control recommendations per threat • Threat tree visualization • Architecture review reporting • Export to compliance frameworks (GDPR data protection, ISO27001)
Methodology
- 1. Architecture analysis: identify components, flows, trust boundaries 2. DFD construction with all elements 3. Threat enumeration using STRIDE: - Spoofing: authentication weaknesses - Tampering: data integrity risks - Repudiation: audit log gaps - Information disclosure: encryption gaps - Denial of service: availability risks - Elevation of privilege: authorization gaps 4. Risk scoring and prioritization 5. Control mapping and recommendations 6. Architecture sign-off by security and engineering teams
Key Findings
Microservices architecture threat model: • 34 threats identified • Top threat: unencrypted service-to-service communication (likelihood: HIGH, impact: HIGH) → Risk: 8/10 • Missing: authentication between services (risk: 7.5/10) • Missing: API rate limiting (risk: 7/10) Recommended controls: 1. Implement mTLS between services (30 days) 2. Add API gateway with authentication (45 days) 3. Deploy circuit breaker and rate limiting (21 days)
Business Impact
Unidentified architectural risks lead to breaches post-deployment. This tool catches them during design, when they're cheapest to fix.
Remediation & Improvements
- • Design changes: implement recommendations • Testing: validate controls during architecture review • Re-assessment: threat model after major changes
Lessons Learned
- 1. Threat modeling is architecture work, not security theater 2. STRIDE forces systematic thinking about threat categories 3. Early identification saves 10x the cost vs. post-deployment fixes
Technologies
Tools & Platforms: Python | Flask | D3.js | STRIDE methodology | PASTA analysis
Hiring Relevance: Security Architect, Threat Modeler, Principal Engineer (Security)
View on GitHub
Full implementation, README, and deployment instructions available at:
GitHub Repository →