majiayu000 Security Threat Modeling
Deliver an actionable AppSec-grade threat model specific to the repository, not a generic checklist. Anchor every architectural claim to evidence in the repo and keep assumptions explicit. Prioritize realistic attacker goals and concrete impacts.
Workflow
1. Scope and Extract the System Model
- Identify primary components, data stores, and external integrations from the repo
- Identify how the system runs (server, CLI, library, worker) and its entrypoints
- Separate runtime behavior from CI/build/dev tooling and from tests/examples
- Map in-scope locations and exclude out-of-scope items explicitly
- Do not claim components, flows, or controls without evidence
2. Derive Boundaries, Assets, and Entry Points
- Enumerate trust boundaries as concrete edges between components
- Note protocol, auth, encryption, validation, and rate limiting at each boundary
- List assets that drive risk: data, credentials, models, config, compute resources, audit logs
- Identify entry points: endpoints, upload surfaces, parsers, job triggers, admin tooling
3. Calibrate Attacker Capabilities
- Describe realistic attacker capabilities based on exposure and intended usage
- List assets that drive risk: credentials, PII, integrity-critical state, availability
- Explicitly note non-capabilities to avoid inflated severity
4. Enumerate Threats as Abuse Paths
- Map attacker goals to assets and boundaries
- Focus on: exfiltration, privilege escalation, integrity compromise, denial of service
- Classify each threat and tie it to impacted assets
- Keep the number of threats small but high quality
5. Prioritize with Explicit Reasoning
- Use qualitative likelihood and impact (low/medium/high) with short justifications
- Set overall priority (critical/high/medium/low) using likelihood x impact
- State which assumptions most influence the ranking
6. Validate with the User
- Summarize key assumptions that affect threat ranking or scope
- Ask 1-3 targeted questions to resolve missing context
- Pause and wait for user feedback before producing the final report
7. Recommend Mitigations
- Distinguish existing mitigations (with evidence) from recommended mitigations
- Tie mitigations to concrete locations and control types
- Prefer specific implementation hints over generic advice
8. Quality Check
- Confirm all entrypoints are covered
- Confirm each trust boundary is represented in threats
- Confirm runtime vs CI/dev separation
- Write the final Markdown to
<repo-name>-threat-model.md
Risk Prioritization Guidance
- High: Pre-auth RCE, auth bypass, cross-tenant access, sensitive data exfiltration, key/token theft, sandbox escape
- Medium: Targeted DoS, partial data exposure, rate-limit bypass, log poisoning
- Low: Low-sensitivity info leaks, noisy DoS with easy mitigation, unlikely preconditions