Advanced level · Module 3: Data Security and Privacy · Lesson 1 of 4
Threats and Layered Defence
Identify who might misuse or expose data and how, and plan layered defences.
In this lesson you will
- Create a simple threat model for a database
- Plan defences at network, server, database and application levels
Key concepts
threat modelattack surfacedefence in depthinsider risk
The lesson
A threat model asks: what data do we hold, who could harm it, how, and what would it cost? For health data, threats include stolen laptops, leaked backups, weak passwords, curious insiders and SQL injection in an application.
Defence in depth layers protections: network restrictions, encrypted connections, strong authentication, least-privilege roles, row-level policies, auditing and safe application code. If one layer fails, others still protect the data.
Many incidents involve people inside the organisation, often by mistake — an exported spreadsheet shared too widely. Controls should make the safe path the easy path.
Step by step
- List the sensitive data in the health database.
- List likely threats and their impact.
- Map existing and missing defences to each threat.
- Prioritise the missing defences.
Practice activity
Write a one-page threat model for the health programme database.
Expected result: A prioritised threat model with a planned defence for each serious threat.
Check your understanding
-
What is defence in depth?
Show answer
Layering several protections so one failure does not expose the data.
-
Name two common causes of data exposure.
Show answer
For example leaked backups or exports and weak or shared passwords.
Taught live by an instructor — online or in person. Free course lessons are for self-study and do not lead to a certificate — see registration options.