Operating System
Runs everything on the machine and controls its files, users and network.
What It Is
The operating system runs every program on the machine and decides what each one may do. It controls the files, the user accounts, the memory and the network. Windows Server and Linux are the usual choices for servers. Its core, the kernel, has full control of the machine.
Everything above it, from the runtime and the servers to the containers and the apps, asks the operating system for what it needs. The operating system in turn runs on hardware, either the physical machine or a virtual machine that a hypervisor provides.
Its patches are yours on your own servers and on cloud virtual machines. Only a managed service, where you never see the operating system, moves them to the provider.
- App
- Framework
- Web Server
- Runtime
- Containers
- OS
- Hypervisor
- Firmware
- Hardware
- Data
On This Layer
These are the technologies on the Operating System layer that this topic covers. Open one to see what it runs on, how to spot it and what a flaw in it reaches.
How Far a Flaw Reaches
A flaw in the operating system, its kernel above all, reaches every application, service and container on that machine. A flaw that spreads over the network, as EternalBlue did, can reach every unpatched machine it can connect to.