Agentic AI security curriculum · Security overview
Quarterly Security Review Checklist: Keeping Defense-in-Depth Alive
Module 20 of 20 · Agentic AI Security Curriculum · May 2026
How to use this module
Use it as self-paced study or as instructor-led training. YAML, commands, and policy excerpts are illustrative; map them to your cloud, mesh, identity provider, and agent runtime—substitute your own names, namespaces, and tools while preserving the control intent.
Estimated time: ~40 minutes reading; add time for linked standards and team discussion.
Learning objectives
By the end of this module, you should be able to:
- Run a periodic defense-in-depth review across supply chain, runtime, and data.
- Assign accountable owners per control domain.
- Capture evidence suitable for audits and customer security questionnaires.
Prerequisites
Defense-in-depth is not a set-it-and-forget-it architecture. It requires continuous validation and maintenance. This final capstone guide provides the operational checklist that must be executed quarterly to keep the entire security posture effective over time.
Quarterly Review Cadence
Perform this full review every three months, or after any major change (new vertical, new proxy backend, Helm upgrade, or Kubernetes version bump). Assign a named security owner responsible for completion and documentation.
1. Supply Chain & Image Verification
Verify all running images are pulled from Harbor with valid Cosign signatures. Confirm allowlist-only resolution is enforced and no external registries are in use. Review Trivy/OSV-Scanner results for new critical vulnerabilities. Validate SBOMs exist for all production images and model weights.
2. Admission Control & Runtime Policies
Check Kyverno policies are active and in “Enforce” mode. Confirm all MCP and sandbox pods use Kata runtime. Verify model weight verification init containers are functioning on inference pods. Review and approve any temporary namespace exemptions.
3. Identity & Zero Trust Controls
Audit Vault dynamic secret leases and revoke any orphaned credentials. Rotate JWT signing keys if due. Verify ATR claim enforcement is working on a sample of MCP tool calls. Confirm YubiKey signing requirement is enforced on all Helm chart changes.
4. Network & Containment
Review Istio ServiceEntries and egress allowlists against current needs. Validate default-deny NetworkPolicy is blocking unauthorized traffic. Check Kiali for unexpected east-west connections. Confirm mTLS is in strict mode everywhere.
5. Monitoring & Observability
Review Wazuh and Falco alert tuning — reduce noise, improve signal. Check Prometheus metrics for Merkle root verification and Cuckoo filter health. Confirm observability workloads are pinned away from GPU nodes. Test Talon quarantine and release process on a non-production pod.
6. Data Protection & Logging
Verify Presidio redaction is active in the Fluent Bit pipeline. Sample WORM logs to ensure no raw PII is present. Confirm Merkle roots are being recorded for all critical workflows.
7. Backup & Recovery Testing
Perform a full restore test of a primary application instance (including memory, documents, and audit trails). Document restore time, success rate, and any issues. Verify 3-2-1+ backup strategy is functioning.
8. STRIDE & OWASP Review
Update the living STRIDE threat model with any new components. Re-map OWASP Agentic Top 10 risks to current controls. Document any new threats and required mitigations.
9. Documentation & Runbooks
Confirm all PICERL runbooks are current. Verify out-of-band communication (Matrix/Mattermost) is tested and ready. Ensure this quarterly checklist itself is up to date.
Key Takeaways
Security is a continuous process, not a destination. Quarterly reviews with a named owner and documented results prevent drift and degradation. Every layer — supply chain, admission, network, runtime, monitoring, and recovery — must be actively validated. Treat the full defense-in-depth stack as a living system that requires ongoing care.
Completing this checklist keeps your organization’s security posture strong, auditable, and ready for both current and future threats.
End of curriculum
Further reading (vendor-neutral)
These resources are independent of any single product; use them to deepen the topic for audits, architecture reviews, or procurement discussions.
Commercial training use
You may reuse this curriculum internally or in paid consulting / training engagements. Keep examples aligned to the customer’s actual stack; substitute your own runbooks, tool names, and compliance frameworks (SOC 2, ISO 27001, sector regulators) where cited examples use a reference architecture only.