Trust boundaries and threat model

Review questions

Trust boundaries and threat model — Integrated Summary

Zero-trust architecture starts by naming the resource, operation and trust crossing, not a network address. A flow inventory follows copies, automated jobs and third parties as well as users. Each crossing needs an identity, resource, action, context, decision, enforcement point and testable record. Threat modeling distinguishes privilege abuse likelihood from impact, while shared responsibility separates provider infrastructure from customer configuration, identities and data. A defensible architecture decision states unknown assumptions, alternatives, a permitted request, a forbidden request and evidence for both.

Review questions

Test your understanding with these questions. Marking and saved results are available with a free account.

  1. Question 1For a booking inventory, what record demonstrates an analytical copy crossing into another account?
  2. Question 2A team wants to protect one report. What is the specific protect surface?
  3. Question 3Two services share a secret. Which threat increases if it leaks?
  4. Question 4The provider encrypts storage, but the customer grants broad decrypt rights. Who must review that role?
  5. Question 5A team compares two paths; one bypasses enforcement. What is the next decision step?
  6. Question 6A nightly job has no human user. Which requester identity fits?
  7. Question 7A read request arrives after a user role change. Which attribute should determine the decision?
  8. Question 8Privilege approval expired, yet an old session still works. What test matters?
  9. Question 9The engine permits requests, but a legacy service never calls it. Where is the gap fixed?
  10. Question 10Correct denials improve and p95 falls, but an export bypass appears. Do you expand?
  11. Question 11An older backup needs a previous key. What policy fits?
  12. Question 12The network permits a service to port 443; what further test is needed?
  13. Question 13An approved API endpoint redirects to an unapproved domain. What is the decision?
  14. Question 14An image signature validates, but its build is unknown. Which evidence is missing?
  15. Question 15The database was restored, but an old identity can read it. Is recovery complete?
  16. Question 16Decision and execution counts differ. What is the first investigation?
  17. Question 17After a project change, backup identity egress rises. Which signal needs examination?
  18. Question 18An account clock is four minutes slow. What correction precedes event ordering?
  19. Question 19A suspected identity supports a critical report. What containment is proportionate?
  20. Question 20A legitimate request works after an incident, but the denial test failed because the target was down. What is recovery status?
  21. Question 21Two services share an admin token. What initial migration dependency matters?
  22. Question 22Access control is listed, yet indexing reads full contracts. What is implementation evidence?
  23. Question 23One option is fast but has a bypass; another is safe but breaches p95. What decision follows?
  24. Question 24An exception is closed manually, but a template restores the role. What guard test is needed?
  25. Question 25Which evidence supports closing a migration wave?