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Defence Stack – Practical Controls
Defence Stack – Practical Controls The layers that stop malware, from the email gateway to the endpoint. Email filtering and macro blocking. EDR /antivirus on each machine. Least privilege. Patching. Offline, tested backups as the last resort. In October 2026, Osaka Metropolitan University had a lar
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What it is
The layers that stop malware, from the email gateway to the endpoint.
Layers
Email filtering and macro blocking. EDR/antivirus on each machine. Least privilege. Patching.
Offline, tested backups as the last resort.
Real incident
In October 2026, Osaka Metropolitan University had a large IT outage.
Public reporting linked it to a security incident. The lesson: layered defence and good backups keep services running.
| Layer | What | Why |
|---|---|---|
| Email filtering + attachment sandbox | Stop initial phish macros/links | Most SME malware still starts in inbox |
| Patch OS + browsers + Office | Close worm/drive-by holes | WannaCry-class lessons |
| AV / EDR | Signature + behaviour | Fileless needs behaviour |
| Application allowlisting | Only approved binaries | Cracked tools / random EXE fail |
| Least privilege | Users not local admin | Ransomware blast radius shrinks |
Learn more in the lesson: 39.6 Defence Stack – Practical Controls