The Life Starter
Sign up
Grade 9 · unit review

Review: Build a Threat and Recovery Model

Model a private-record endpoint that lacks authorization and a usable backup made at hour 5 before failure at hour 8. Select controls and a data-preserving test.

Download reviews and answer keys

Bring the unit skills together

Use these 4 new cases to check your reasoning. Choices are temporary and are not saved to an account, sent to staff or recorded as school grades. Download your current review choices before leaving or reloading.

Unit review questions
1. Accidental deletion of all copies. Which threat-model role is described?
Need a hint?
  • Classify the statement’s role in the threat model before selecting a control.
  • A control name does not prove that a threat or weakness has been addressed.
2. Main and backup copies share the same single failure point. Which control addresses the weakness?
Need a hint?
  • Choose the control that directly addresses the supplied weakness.
  • Encryption alone does not repair a server that gives authorized plaintext to the wrong requester.
3. Paper clock: last usable backup at hour 13; failure at hour 20. Maximum later-work time absent from this backup?
Need a hint?
  • Subtract last completed backup time from the failure time in matching units.
  • A usable backup can still omit work created after it was made.
4. Only a copy timestamp is checked. Which recovery evidence is present?
Need a hint?
  • Test a copied synthetic record in an isolated destination and compare its expected content.
  • Do not restore test fixtures over production records to prove recovery.

The download contains your current choices and any checked feedback. Keep the separate transfer-task work in your own document; downloading its instructions does not mark it complete.

Use the skills in a new task

Model a private-record endpoint that lacks authorization and a usable backup made at hour 5 before failure at hour 8. Select controls and a data-preserving test.

Work on paper or in your own document. Explain the choices you made.

  • Use only supplied fictional inputs and state the relevant rule.
  • Include labeled steps or evidence for each decision.
  • Name one limitation or tempting mistake.
  • Check that the result meets the task and revise a justified error.
Compare with a model response

The project contents are assets and missing authorization is a vulnerability. Add a server permission check. The backup’s gap is 3 hours. Test restoration with synthetic records in an isolated destination, keeping real work intact.

A different response can also meet the criteria. Compare the evidence and reasoning, rather than copying the wording.