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Module 6 of 12 · 56 min

Endpoint Identity, Network, and Secrets Security

Protect a self-hosted model endpoint with explicit principals, least privilege, bounded networks, managed secrets, abuse controls, and auditable revocation.

Core concept

By the end

You will be able to

  • Threat-model identities, data flows, management planes, artifacts, clients, operators, and dependent services.
  • Authenticate workloads and people, authorize each action, and keep enforcement outside model prompts.
  • Design network, secret, resource, data, and administrative controls that fail closed.
  • Test unauthorized, over-privileged, exhausted, injected, revoked, and incident conditions with recoverable evidence.
01

Map every trust boundary and principal

Diagram clients, gateways, inference servers, runtimes, artifact stores, registries, identity systems, secret stores, telemetry, administrators, automation, and update paths. Mark network hops, data classifications, credentials, management interfaces, external dependencies, and where untrusted prompts, files, retrieved text, or tool output enter.

Name human, workload, device, service, and break-glass principals separately. A shared API key erases attribution and complicates revocation. Record who may discover models, invoke inference, change configuration, promote artifacts, read telemetry, rotate secrets, approve releases, and execute recovery.

02

Enforce identity and authorization outside the model

Use verified workload or user identity appropriate to the environment, short-lived credentials where supported, audience and issuer checks, scoped roles, explicit deny behavior, and re-authentication for consequential administration. Bind policy to stable identities rather than network location alone.

Treat prompts and model output as untrusted data, never as authorization. The model cannot grant access, select its own credentials, or approve an external action. Validate object, property, and function authorization at the gateway or application for every request.

03

Bound network exposure and management paths

Listen only on required interfaces, place authentication before inference, encrypt traffic where the threat model requires it, restrict ingress and egress, separate management from serving, and allow outbound destinations by purpose. Verify DNS, proxies, certificates, service discovery, and time synchronization as dependencies.

A container port or cluster service can become reachable beyond its intended boundary through publishing, routing, load balancers, host networking, or permissive network policy. Test reachability from allowed and denied locations and verify that administrative endpoints are not exposed through the serving route.

04

Manage secrets, sensitive data, and resource abuse

Keep secrets out of images, model repositories, prompts, logs, traces, command lines, and static examples. Deliver them through the approved secret mechanism, scope them to one purpose, rotate and revoke them, audit access, and prove that replaced credentials stop working.

Minimize and classify request and response data, redact telemetry, set retention and deletion, isolate caches, and define incident handling. Enforce body, context, output, concurrency, rate, queue, compute, memory, and time limits. OWASP API Security includes unrestricted resource consumption among critical API risks; model endpoints make that risk expensive and operationally consequential.

05

Test denial, revocation, containment, and recovery

Test missing, expired, wrong-audience, forged, and revoked credentials; cross-role and cross-object access; management-route access; oversized and adversarial inputs; prompt injection; secret leakage; egress attempts; repeated expensive requests; malformed streams; and telemetry redaction. Confirm safe status codes, no side effects, bounded cost, and useful audit evidence.

Exercise credential rotation, principal suspension, emergency route disablement, secret compromise, artifact quarantine, network isolation, and restoration from a known configuration. Preserve evidence and reconcile in-flight work. Security is incomplete if access can be denied but not reliably restored through an approved recovery path.

Practice activity

Build and test a synthetic endpoint security plan

  1. Draw the serving and management data flows with principals, credentials, trust boundaries, data classes, stores, and outbound dependencies.
  2. Create a least-privilege role matrix for invoke, discover, configure, promote, observe, approve, rotate, revoke, and recover.
  3. Write network, secret, data, resource, audit, and break-glass policies with explicit deny behavior.
  4. Create unauthorized, over-privileged, exhaustion, injection, leakage, revocation, and recovery test cases with expected evidence.
  5. Run the cases against a paper fixture and record every control that lacks an owner or observable result.

What to produce

  • A threat and data-flow model with principals, boundaries, assets, threats, and mitigations.
  • A role, network, secret, data, resource, audit, and break-glass control matrix.
  • A negative-test and revocation report with expected results, residual risks, recovery, and accountable owners.

Reflect before continuing

Which control still depends on trusting model output, and how will you move enforcement outside the model?

Evidence

Sources and verification

Knowledge check

Make it stick.

Pass at 80%

Choose the strongest answer for each question. Your attempts become part of your device-local transcript.

01Where should authorization be enforced?
02Why are shared long-lived API keys weak for multi-user administration?
03What should a network test include?
04Where should secrets not appear?
05Which control addresses expensive request abuse?
06What completes a revocation test?