High School IntermediateModule I9Lesson 2 of 8

I9.2 Threat Modeling and Attack Surface Review

Learn how fictional development teams map assets, users, data flows, trust boundaries, entry points, dependencies, privileges, misuse cases, existing controls, evidence gaps, business impact, and residual risk before choosing and validating defensive controls.

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Threat Modeling and Attack Surface Review

High School IntermediateI9: Secure Coding Basics • Lesson 2 of 8

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Professional Hook

Threat Modeling Makes Security Decisions Visible Before Failure

A fictional application may have strong login controls while a teacher can request another teacher’s record. A secure API may still send data to an overbroad third-party integration. A protected administrator route may rely on an unreviewed recovery process. Threat modeling asks where assumptions change, what could fail, which controls exist, what evidence supports them, and who owns the risk.

Weak model

“The fictional application is internal and uses login, so the remaining risk is low.”

Strong model

“Map each identity, object, route, trust boundary, privileged action, data flow, dependency, control, misuse case, evidence source, owner, and residual risk.”

Objective 1

Explain how fictional threat modeling connects users, assets, data flows, trust boundaries, entry points, dependencies, privileges, misuse cases, and business impact.

Objective 2

Distinguish attack surface, threat event, weakness, control, evidence, likelihood, impact, residual risk, assumption, and evidence gap.

Objective 3

Build a fictional data-flow and trust-boundary model for a web application without probing, exploiting, or testing any real system.

Objective 4

Prioritize fictional risks using evidence strength, exposure, control effectiveness, asset value, business consequence, and remediation ownership.

Objective 5

Create a professional fictional Threat Model and Attack Surface Review with findings, owners, validation, monitoring, exceptions, and closure criteria.

Why This Matters

The Most Important Risks Often Appear Between Components

Fictional security failures frequently occur when one component trusts another component’s identity, role, input, output, route, destination, session, file, secret, or business decision. By mapping transitions and assumptions, teams can choose controls before unsafe patterns become difficult to remove and can design evidence that proves whether those controls work.

Asset Review

Eight Assets with Different Protection Needs

Student-support records

Fictional nonpublic summaries and case notes used by teachers and authorized support staff.

Security needs

Confidentiality, object authorization, tenant isolation, accurate updates, limited retention, controlled export, and auditability.

Failure impact

Unauthorized viewing, incorrect changes, privacy harm, loss of trust, or reporting errors.

Owner: Student Services Technology

Teacher and administrator identities

Fictional accounts, roles, factors, devices, sessions, permissions, and recovery state.

Security needs

Strong authentication, secure recovery, session rotation, revocation, least privilege, and access review.

Failure impact

Unauthorized actions, wrong-role access, account misuse, or inability to attribute activity.

Owner: Identity and Access Team

Application API

Fictional service enforcing input contracts, authorization, workflow rules, and data access.

Security needs

Schema validation, object authorization, safe operations, rate controls, error safety, logging, and service identity.

Failure impact

Data exposure, incorrect updates, service abuse, broken workflows, or unreliable evidence.

Owner: Web Platform Team

Reporting and export workflow

Fictional district reports, export jobs, files, approvals, and business records.

Security needs

Privileged access, reauthentication, dual approval, idempotency, secure files, expiry, and monitoring.

Failure impact

Unapproved data export, duplicate actions, incorrect reporting, or privacy and compliance impact.

Owner: District Applications Team

Announcement and messaging content

Fictional plain text, approved rich text, notifications, previews, and audience selections.

Security needs

Safe rendering, sanitization, approval, destination control, audience authorization, and browser policy.

Failure impact

Misleading content, unsafe rendering, wrong audience, deceptive links, or operational confusion.

Owner: Communications Technology

Secrets and service identities

Fictional API credentials, signing keys, database identities, certificate keys, and deployment identities.

Security needs

Managed storage, narrow access, rotation, audit logging, no code exposure, and retirement.

Failure impact

Service impersonation, unauthorized data access, deployment compromise, or loss of trust.

Owner: Platform Engineering

Application availability

Fictional login, record access, support workflows, reporting, recovery, and monitoring services.

Security needs

Capacity controls, graceful failure, dependency resilience, rollback, recovery, and health monitoring.

Failure impact

Interrupted support, delayed decisions, user frustration, operational cost, or missed deadlines.

Owner: Infrastructure Operations

Security and audit evidence

Fictional request IDs, identity events, application decisions, database transactions, alerts, cases, and owner approvals.

Security needs

Integrity, time accuracy, privacy, retention, access control, source health, correlation, and safe display.

Failure impact

Weak investigations, missing accountability, false conclusions, delayed response, or unsupported closure.

Owner: Security Operations

Trust Boundaries

Eight Places Where Assumptions Must Be Revalidated

Public browser to reverse proxy

Fictional requests move from an untrusted client environment into owned infrastructure.

Required checks

TLS, host validation, request limits, safe headers, method rules, content type, routing, request ID, and edge logging.

Assumption

The reverse proxy is the only approved external entry point.

Evidence

DNS, certificate, listener, route policy, request logs, and architecture inventory.

Reverse proxy to application API

Fictional network and forwarding context becomes application identity, session, route, object, and business context.

Required checks

Trusted forwarded headers, authenticated session, input schema, authorization, anti-forgery control, and safe errors.

Assumption

Only approved proxies can set trusted client and scheme headers.

Evidence

Proxy trust configuration, application logs, route tests, and deployment template.

Application API to identity service

Fictional application requests depend on external identity claims, factors, session state, and risk decisions.

Required checks

Issuer, audience, signature, time, account state, factor, session, revocation, and application policy.

Assumption

The application validates current identity metadata rather than trusting client-supplied role claims.

Evidence

Identity configuration, token metadata, session logs, policy records, and negative tests.

Application API to database

Fictional user intent becomes service-authorized data operations under a service identity.

Required checks

Object and tenant authorization, prepared operations, least privilege, transaction rules, row limits, and audit logging.

Assumption

The database accepts requests only from approved service identities.

Evidence

Service policy, prepared-operation record, database logs, network policy, and access review.

Application to third-party integration

Fictional owned data and requests move to a provider with separate ownership and security practices.

Required checks

Business need, exact destination, authentication, minimum data, schema validation, timeout, retry, error handling, monitoring, and contract ownership.

Assumption

The provider handles only the approved data and does not become a trusted authorization source.

Evidence

Integration inventory, data-flow record, contract, configuration, test, and provider-owner review.

Administrator to privileged function

Fictional ordinary authenticated access becomes high-impact export, role, account, configuration, or recovery authority.

Required checks

Privileged role, reauthentication, step-up verification, dual approval, confirmation, idempotency, and enhanced logging.

Assumption

Privileged actions cannot be completed through ordinary user routes.

Evidence

Role policy, approval record, session event, transaction log, and positive and negative tests.

Stored content to browser rendering

Fictional database or message content becomes HTML text, rich text, attribute, URL, preview, notification, or export output.

Required checks

Output-context handling, safe binding, sanitization, destination allowlist, content policy, isolation, and viewer review.

Assumption

Stored content is treated as untrusted at every new output boundary.

Evidence

Source-to-sink map, component review, sanitizer policy, browser result, and regression tests.

Production service to monitoring platform

Fictional operational events become centralized evidence used for detections and investigations.

Required checks

Structured fields, request correlation, redaction, source health, time normalization, retention, access control, and safe rendering.

Assumption

Monitoring receives complete and timely events from all critical paths.

Evidence

Source inventory, parser status, event counts, time checks, retention, and access review.

Core Concept

Use the Asset–Flow–Boundary–Threat–Control Chain

Asset

Which fictional data, identity, service, secret, workflow, decision, or evidence needs protection?

Flow

Where does the fictional asset move, transform, wait, render, or become a business action?

Boundary

Where do fictional identity, ownership, privilege, or trust assumptions change?

Threat

Which fictional misuse, failure, mistake, defect, dependency, or unsafe condition could occur?

Control

Which fictional design, code, configuration, process, monitoring, or owner reduces the risk?

Evidence

Which fictional test, log, transaction, owner review, and business record proves the result and residual risk?

Attack Surface

Eight Entry-Point Groups to Review

Sign-in and recovery

Inputs and actions

Fictional account identifiers, factors, recovery evidence, devices, sessions, and redirects.

Threats

Account guessing, unsafe recovery, session fixation, misleading redirects, or weak revocation.

Controls

MFA, rate controls, recovery separation, rotation, safe redirects, device and risk policy, and monitoring.

Validation

Approved sign-in and recovery work; invalid factors, expired sessions, unapproved redirects, and disabled accounts fail.

Record lookup and editing

Inputs and actions

Fictional record IDs, filters, fields, text, attachments, and workflow actions.

Threats

Unassigned record access, wrong-tenant access, invalid updates, unsafe files, or excessive data exposure.

Controls

Server-side object authorization, schemas, file policy, least privilege, field allowlists, and safe errors.

Validation

Assigned records work; unassigned, wrong-tenant, malformed, excessive, and unauthorized requests fail before data access.

Search and reporting

Inputs and actions

Fictional queries, filters, sort choices, date ranges, page sizes, report types, and export requests.

Threats

Dynamic construction, excessive resource use, unapproved export, duplicate jobs, or sensitive result exposure.

Controls

Strict schemas, server-defined mappings, bound values, quotas, privileged approval, idempotency, and secure files.

Validation

Approved reports work; unsupported choices, excessive ranges, unauthorized roles, and duplicate submissions do not create extra results.

Announcements and messages

Inputs and actions

Fictional plain text, approved rich text, links, audience selection, scheduling, and previews.

Threats

Unsafe rendering, misleading destinations, wrong audience, unauthorized publishing, or stale content.

Controls

Safe binding, narrow sanitization, destination allowlists, audience authorization, approval, expiry, and content policy.

Validation

Approved formatting and audience work; unsupported content and unauthorized publishing are denied.

File upload and download

Inputs and actions

Fictional documents, names, metadata, content types, storage locations, previews, and download actions.

Threats

Unsafe content, misleading files, oversized uploads, public exposure, path mistakes, or long-lived download links.

Controls

Type and size policy, isolated processing, safe names, private storage, authorization, expiry, and viewer isolation.

Validation

Approved files work; unsupported, oversized, unauthorized, expired, and cross-tenant access fail safely.

Administrative console

Inputs and actions

Fictional role changes, account state, exports, configuration, recovery, and approval actions.

Threats

Privilege misuse, hidden sensitive actions, stale sessions, duplicate approvals, or overbroad access.

Controls

Privileged roles, reauthentication, dual approval, confirmation, idempotency, route gating, and detailed evidence.

Validation

Approved administrators succeed; ordinary users, stale sessions, missing approvals, and duplicate requests fail.

API and integration

Inputs and actions

Fictional tokens, service identities, JSON data, callbacks, webhooks, third-party responses, and retries.

Threats

Wrong audience, overbroad scopes, replay, untrusted callbacks, schema drift, or provider outage.

Controls

Exact identity and audience checks, schema validation, replay controls, destination allowlists, timeouts, retries, and monitoring.

Validation

Approved integration messages work; wrong identity, malformed, duplicate, expired, and unapproved-destination cases fail.

Operations and deployment

Inputs and actions

Fictional builds, packages, images, feature flags, environment variables, secrets, migrations, and configuration changes.

Threats

Unsafe dependency, secret exposure, debug mode, drift, wrong identity, excessive ports, or failed rollback.

Controls

Artifact verification, managed secrets, secure baselines, peer approval, least privilege, smoke tests, monitoring, and rollback.

Validation

Approved build and configuration deploy; altered artifacts, debug settings, unnecessary services, and failed health checks block release.

Threat Categories

Eight Questions for Defensive Review

Identity misuse

Could a fictional user, service, device, or session be mistaken for another identity or retain access after trust changes?

Fictional examples

Weak recovery, stale sessions, shared accounts, overbroad service identities, or unvalidated identity claims.

Control focus

MFA, secure recovery, session rotation and revocation, named identities, claim validation, and access review.

Authorization failure

Could a fictional authenticated identity access another object, tenant, action, workflow state, or privilege level?

Fictional examples

Missing object checks, client-trusted roles, exposed administrator routes, or inconsistent API enforcement.

Control focus

Central server-side authorization, tenant isolation, trusted object resolution, least privilege, and negative tests.

Unsafe data interpretation

Could fictional data become query structure, command structure, markup, navigation, file behavior, or configuration?

Fictional examples

Dynamic queries, raw markup, untrusted destinations, unsafe filenames, or configuration injection.

Control focus

Schemas, strict allowlists, parameterization, safe APIs, context output handling, and isolated processing.

Information exposure

Could fictional private data, secrets, internal details, or evidence be returned, logged, cached, exported, or shared too broadly?

Fictional examples

Verbose errors, parent-domain cookies, overbroad exports, secret logging, or public download links.

Control focus

Data minimization, safe errors, redaction, access control, private storage, cache policy, and retention limits.

Integrity and workflow abuse

Could fictional data, approvals, roles, transactions, or records be changed incorrectly or without clear user intent?

Fictional examples

Request forgery, duplicate approval, missing confirmation, weak business rule, or stale workflow state.

Control focus

Anti-forgery controls, authorization, confirmation, reauthentication, idempotency, transaction rules, and audit logs.

Availability and resource exhaustion

Could fictional requests, files, queries, dependencies, retries, or administrative actions reduce service availability?

Fictional examples

Excessive search range, oversized upload, retry storm, slow dependency, unbounded export, or missing capacity limit.

Control focus

Bounds, quotas, timeouts, circuit breaking, queues, graceful failure, capacity monitoring, and recovery.

Dependency and configuration risk

Could fictional packages, services, build steps, runtime settings, certificates, or manual changes weaken the application?

Fictional examples

Unsupported runtime, debug mode, exposed port, stale certificate, broad permission, or compromised package source.

Control focus

Inventory, lockfiles, trusted sources, supported versions, secure baselines, drift detection, and rollback.

Evidence and accountability failure

Could fictional actions occur without reliable identity, request, decision, object, transaction, time, or owner evidence?

Fictional examples

Missing request IDs, incomplete logs, parser failure, shared accounts, weak retention, or unowned alerts.

Control focus

Structured logs, correlation, time accuracy, named identities, source health, retention, access control, and case governance.

Risk Prioritization

Eight Factors for an Evidence-Based Priority

Asset value

Lower concern

Fictional public or low-impact content with easy recovery.

Higher concern

Fictional nonpublic student data, privileged identity, secrets, exports, or critical support workflows.

Evidence

Data classification, business owner, workflow dependency, recovery requirement, and impact statement.

Exposure

Lower concern

Fictional isolated test feature available only to a small approved group.

Higher concern

Fictional public route, broad authenticated population, third-party integration, or internet-facing service.

Evidence

Route inventory, listener, user population, integration list, network path, and access policy.

Exploitability or misuse difficulty

Lower concern

Fictional issue requires several privileged approvals and unusual conditions.

Higher concern

Fictional issue occurs through ordinary browser requests, common user actions, or default workflow behavior.

Evidence

Preconditions, roles, sessions, route behavior, required approvals, and supplied safe test results.

Existing control strength

Lower concern

Fictional independent controls prevent or limit the result and are validated.

Higher concern

Fictional controls are missing, inconsistent, bypassable, unmonitored, or unsupported by evidence.

Evidence

Design, code, configuration, control decisions, positive tests, negative tests, and monitoring.

Scope

Lower concern

Fictional one user, one object, one test environment, or one isolated path.

Higher concern

Fictional many users, tenants, records, routes, environments, or shared services.

Evidence

Affected inventory, user count, object count, tenant list, route list, and deployment map.

Business consequence

Lower concern

Fictional minor inconvenience with no sensitive data or critical workflow effect.

Higher concern

Fictional privacy harm, incorrect decision, unapproved payment, loss of evidence, outage, or legal and trust impact.

Evidence

Business owner, transaction state, user effect, data state, availability, and policy requirement.

Detection and response

Lower concern

Fictional activity is reliably logged, alerted, owned, investigated, and reversible.

Higher concern

Fictional activity may be silent, unattributed, retained briefly, or difficult to reverse.

Evidence

Source health, rule coverage, owner, retention, case process, rollback, and recovery evidence.

Evidence confidence

Lower concern

Fictional conclusion depends on assumptions, stale diagrams, missing logs, or one ambiguous event.

Higher concern

Fictional multiple independent sources support the same conclusion and limitations are documented.

Evidence

Source count, raw records, normalized timeline, user confirmation, system-of-record state, and evidence gaps.

Threat-Model Workflow

Build and Maintain the Model in Six Steps

1

Define scope and assets

List fictional users, data, identities, secrets, services, workflows, environments, owners, and business consequences.

2

Map data and trust boundaries

Draw fictional sources, destinations, protocols, transformations, identities, privilege changes, and storage locations.

3

Inventory attack surface

Review fictional routes, APIs, files, messages, integrations, administrative paths, dependencies, services, and deployments.

4

Describe misuse and controls

Write fictional threat events, preconditions, affected assets, existing controls, evidence, alternatives, and gaps.

5

Prioritize and assign

Evaluate fictional exposure, asset value, control strength, scope, business effect, reversibility, confidence, owner, and due date.

6

Validate and maintain

Run fictional positive and negative tests, monitor, update after changes, review exceptions, prepare rollback, and document residual risk.

Traceable Threat Timeline

Follow a Fictional Object-Authorization Threat from Model to Monitoring

Day 1

Scope

A fictional team defines the student-support portal, administration console, identity service, API, database, proxy, and monitoring platform.

The initial system boundary and major owners are established.

Day 2

Asset review

Student-support records, privileged identities, exports, secrets, availability, and audit evidence are classified as important assets.

Protection priorities are connected to business value.

Day 3

Data flow

The fictional browser sends record requests through the proxy and API to the reporting database.

Several trust boundaries and evidence sources are identified.

Day 4

Attack surface

The team inventories sign-in, recovery, record access, reports, announcements, files, APIs, administrator routes, and deployment paths.

The reachable feature set is documented.

Day 5

Misuse case

TM-07 describes a teacher requesting another teacher’s assigned student record.

An object-authorization failure scenario is made specific and testable.

Day 6

Existing control

The fictional route verifies authentication and role but does not resolve the trusted assignment relationship.

The existing control is incomplete.

Day 7

Negative test

A fictional teacher retrieves an unassigned record in the safe test environment.

The threat event produces a confirmed unauthorized result under the supplied conditions.

Day 8

Risk review

The team rates the issue high because the data is nonpublic, the route is broadly available to teachers, and the result is reproducible.

Asset value, exposure, control weakness, and evidence strength drive priority.

Day 9

Containment

The feature is blocked from release while the central authorization policy is corrected.

A narrow release control prevents known exposure.

Day 10

Remediation

The server resolves tenant, record, assignment, role, action, and session using trusted data.

The control now matches the misuse case and security requirement.

Day 11

Positive test

A fictional teacher can retrieve an assigned record.

Legitimate workflow remains available.

Day 11

Negative test

Unassigned, wrong-tenant, wrong-role, expired-session, and missing-session requests are denied before data access.

Several related misuse cases are controlled.

Day 12

Threat model update

The data-flow diagram, attack-surface inventory, risk record, tests, and owner status are updated.

The threat model becomes traceable to remediation and validation.

Day 19

Monitoring

Assigned access remains normal and no unexplained cross-tenant result appears.

Short-term operational evidence supports the control.

Day 30

Change review

A new third-party messaging integration triggers a threat-model and data-flow update.

The model remains a living lifecycle artifact.

Key Vocabulary

Threat Modeling and Attack Surface Terms

Threat model

A fictional structured review of assets, users, data, components, trust boundaries, entry points, dependencies, possible failures, controls, and residual risk.

Attack surface

The fictional collection of reachable interfaces, features, accounts, services, files, dependencies, trust transitions, and administrative paths that could affect security.

Asset

A fictional system, data set, identity, secret, service, workflow, decision, or business capability that requires protection.

Trust boundary

A fictional transition where data, identity, privilege, ownership, or control assumptions change and must be revalidated.

Entry point

A fictional interface through which data, requests, files, messages, users, services, or administrators interact with the system.

Threat event

A fictional condition or action that could cause loss of confidentiality, integrity, availability, privacy, accountability, or business trust.

Misuse case

A fictional scenario describing how a feature, role, workflow, dependency, or integration could be used incorrectly, abused, or misunderstood.

Existing control

A fictional design, code, configuration, process, monitoring, or governance measure already reducing the risk.

Residual risk

The fictional risk remaining after existing and planned controls are considered.

Assumption

A fictional statement believed to be true for the model but requiring validation or periodic review.

Evidence gap

A fictional missing, stale, inconsistent, or unavailable record that limits confidence in the threat model or risk decision.

Abuse case

A fictional defensive test scenario that checks how the system behaves when inputs, identities, objects, timing, or workflows are used in an unsafe or unauthorized way.

Fake Dashboard

Fake Threat Model and Attack Surface Dashboard

Training dashboard for the fictional Meadowbrook student-support portal.

Modeled assets

24

Fictional data, identities, services, secrets, workflows, availability, and evidence assets.

Trust boundaries

17

Browser, proxy, application, identity, database, third-party, privileged, rendering, and monitoring transitions.

Open threat items

9

Authorization, input, rendering, recovery, export, dependency, configuration, availability, and evidence-gap reviews.

Fake SOC Alert

Threat Model Finds Missing Object-Assignment Check

Source: Fake Threat Modeling Review Console • Time: 10:30 AM

High Severity
A fictional misuse case describes a teacher requesting another teacher’s assigned student-support record. The route verifies authentication and teacher role but does not resolve the trusted assignment relationship. A supplied negative test reproduces unauthorized access in the safe test environment.
Defensive recommendation: Block release of the affected feature, preserve architecture and test evidence, implement centralized server-side tenant and object authorization, test assigned and unassigned access across roles and sessions, update the threat model and data flow, monitor, document residual risk, and obtain owner approval.

Fake Log Panel

Fake Threat Model Traceability Timeline

training-log-viewer.log
DAY1 SCOPE systems='portal,admin,identity,api,database,proxy,monitoring'
DAY2 ASSET student_support_records='high_value'
DAY3 DATA_FLOW browser='proxy' proxy='api' api='database'
DAY4 ATTACK_SURFACE entries='signin,records,reports,announcements,files,api,admin,deploy'
DAY5 MISUSE_CASE id='TM-07' scenario='teacher_unassigned_record'
DAY6 CONTROL authentication='present' role_check='present' assignment_check='missing'
DAY7 NEGATIVE_TEST unassigned_record='allowed'
DAY8 RISK asset='nonpublic' exposure='teacher_population' reproducible='true' priority='high'
DAY9 RELEASE_GATE result='blocked'
DAY10 REMEDIATE tenant='verified' assignment='verified' object='verified' action='verified'
DAY11 POSITIVE_TEST assigned_record='pass'
DAY11 NEGATIVE_TEST unassigned='deny' wrong_tenant='deny' wrong_role='deny' expired='deny'
DAY12 MODEL_UPDATE data_flow='updated' risk='updated' tests='linked' owner='assigned'
DAY19 MONITOR unexplained_cross_tenant_results='0'
DAY30 CHANGE_REVIEW third_party_messaging='model_update_required'

Training note: this is fake data for defensive analysis practice only.

Analyze the Evidence

Which Threat-Model Conclusion Is Best Supported?

The fictional student-support records are classified as nonpublic.
The route is available to authenticated teacher accounts.
The route checks authentication and teacher role.
The route does not verify the trusted assignment relationship.
A supplied negative test retrieves an unassigned record in the safe test environment.
The feature is blocked from release.
The remediation verifies tenant, record, assignment, role, action, and session state.
Assigned access passes while unassigned, wrong-tenant, wrong-role, expired-session, and missing-session requests are denied.

Which conclusion is strongest?

Common Mistakes

Mistakes That Weaken Threat Models

Treating a fictional threat model as a one-time diagram rather than a living decision and evidence record.
Listing generic threats without connecting them to exact assets, entry points, trust boundaries, users, objects, and business workflows.
Calling every feature an attack surface without identifying who can reach it, what it accepts, and which controls apply.
Assuming internal users, services, networks, or stored data are automatically trusted.
Scoring risk before confirming asset value, exposure, preconditions, existing controls, scope, and evidence quality.
Treating a code weakness as proof of successful harmful use or treating a blocked test as proof that every path is safe.
Ignoring third-party, administrative, recovery, deployment, legacy, preview, export, error, and monitoring paths.
Using only happy-path tests and skipping wrong-role, wrong-tenant, expired, duplicate, malformed, cross-origin, and failure cases.
Assigning all remediation to the security team instead of the accountable application, identity, platform, data, or business owner.
Closing a threat after one code change without updating architecture, tests, monitoring, exceptions, rollback, and residual risk.
Publishing real architecture, routes, hostnames, identities, source code, secrets, logs, or student data in a portfolio artifact.
Creating exploit payloads or probing real systems instead of using supplied fictional evidence and safe defensive scenarios.

Safe Practice Lab

Build a Fictional Threat Model and Attack Surface Review

Fictional Evidence Set

Meadowbrook Student-Support Portal

Review forty-two supplied fictional records covering assets, users, data flows, trust boundaries, entry points, dependencies, identities, privileges, misuse cases, code and configuration controls, tests, monitoring, owners, exceptions, and residual risk.

Required Analysis

  1. Define fictional scope, owners, environments, users, assets, data, secrets, and business workflows.
  2. Create a data-flow diagram with sources, destinations, protocols, identities, storage, transformations, and trust boundaries.
  3. Inventory routes, APIs, files, messages, third parties, administrative paths, dependencies, services, and deployments.
  4. Write at least eight misuse cases with preconditions, assets, controls, evidence, alternatives, and gaps.
  5. Prioritize risks using asset value, exposure, control strength, scope, business consequence, detection, reversibility, and confidence.
  6. Document owners, remediation, positive tests, negative tests, monitoring, rollback, exceptions, residual risk, and closure criteria.
Use only supplied fictional evidence. Do not probe real systems, create exploit payloads, access accounts, modify applications, or publish real architecture, routes, code, secrets, logs, user records, hostnames, integrations, or private organizational data.

Scenario Decision Lab

A Threat Model Assumes Internal Users Are Trusted

A fictional design note says object authorization is unnecessary because only teachers can access the application.

Scenario Decision Lab

A New Third-Party Messaging Integration Is Proposed

A fictional provider will receive selected announcement text and audience identifiers, but the existing threat model does not include the provider.

Defender Habits

Threat Modeling and Attack Surface Review Checklist

Check Your Understanding

I9.2 Mini Quiz: Threat Modeling and Attack Surface Review

Choose your answers first. Explanations appear only after submission.

1. What is the primary purpose of a fictional threat model?

2. What makes a fictional trust boundary important?

3. Which item belongs in an attack-surface inventory?

4. A fictional route checks authentication but not object assignment. What is the strongest conclusion?

5. Which risk-prioritization approach is strongest?

6. When should a fictional threat model be updated?

7. Which portfolio practice is safest?

Portfolio Prompt

Portfolio Prompt

Create a fictional Threat Model and Attack Surface Review using at least forty-two architecture, asset, user, data-flow, trust-boundary, route, API, file, integration, dependency, misuse-case, control, test, monitoring, owner, exception, and residual-risk records. Include an architecture diagram, data-flow map, attack-surface inventory, eight misuse cases, risk ranking, evidence references, owners, remediation, positive tests, negative tests, rollback, evidence gaps, and closure criteria.

Use only fictional applications, users, routes, systems, data, identities, dependencies, logs, tests, and organizations.
For every threat item, state the asset, boundary, entry point, precondition, existing control, evidence, impact, owner, and residual risk.
Keep possible threat, confirmed weakness, successful harmful use, control result, data state, user effect, and business impact separate.
Do not include real architecture, hostnames, source code, credentials, secrets, logs, student records, or private organizational information.

Key Takeaways

What You Should Remember

1.Threat modeling connects fictional assets, data flows, trust boundaries, entry points, misuse cases, controls, evidence, owners, and residual risk.
2.Attack surface includes public, authenticated, administrative, integration, file, dependency, deployment, recovery, and monitoring paths.
3.Authentication does not replace object authorization, tenant isolation, workflow checks, or user-intent controls.
4.Risk priority should reflect asset value, exposure, control strength, scope, business consequence, detection, reversibility, and evidence confidence.
5.A threat model is a living lifecycle artifact that must change when the system, users, data, dependencies, environment, or business workflow changes.
6.Strong validation preserves legitimate workflows while proving unsafe and unauthorized conditions are denied.

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