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Lab 00 — Set Up Your Lab

LabSeptember 12, 2026

Start from a laptop with nothing installed and finish with a safe, self-contained Kali machine you can practise in. No prior setup assumed — every click is spelled out.

NyxHonest note: Steven wrote this up before running it start to finish himself. I’m keeping an eye on him.

● Start hereIdea buildFor complete beginnersTime ~45 min (mostly downloads)Cost $0

0 / 6 steps

What you’re building

A virtual machine — a whole second computer running Kali Linux (the distribution loaded with security tools) inside a window on your own PC. It’s walled off from your real system, you can break it freely, and if you ever wreck it you roll back to a clean copy in seconds. This is the sandbox every other lab runs in.

⚠ Why a VM and not the real thing. Security tools poke at systems in ways you don’t want touching your everyday computer or network. The VM keeps all of it in a box. Keep it that way: only ever point tools at machines inside your lab or at hosts that explicitly allow it.

Steps

01Install VirtualBox

VirtualBox is the free program that runs virtual machines. It’s made by Oracle and it’s free for personal use.

  1. Go to virtualbox.org/wiki/Downloads
  2. Under VirtualBox platform packages, click Windows hosts (or macOS / Intel hosts if you’re on a Mac). An installer downloads.
  3. Open the downloaded file and click Next → Next → Yes → Install. Accept the defaults; it’s safe to say yes to the network warning during install.
  4. When it finishes, let it launch. You should see the Oracle VirtualBox Manager window, empty for now.

On a work laptop? If the installer is blocked, your machine is locked down by IT — use a personal computer for the lab. Don’t fight a managed device.

02Download the ready-made Kali machine

You could install Kali from scratch, but there’s a shortcut: Kali publishes a pre-built VirtualBox image. You download one file and import it — no OS install to sit through.

  1. Go to kali.org/get-kali and pick Virtual Machines.
  2. Click the VirtualBox download (a large .7z file, ~3–4 GB — this is the slow part).
  3. You’ll need 7-Zip to unpack a .7z. Install it, then right-click the downloaded file → 7-Zip → Extract Here. You get a folder with a .vbox file inside.

Why the prebuilt image: a from-scratch install means partitioning, drivers, and guest-additions headaches. The prebuilt VM skips all of it and boots straight to a working desktop. Start here; do a manual install later if you ever want to.

03Add it to VirtualBox and start it

  1. In VirtualBox Manager, double-click the .vbox file you extracted (or use Machine → Add and point it at that file). Kali appears in the left-hand list.
  2. Select it and click the green Start arrow.
  3. A window opens and Kali boots to a login screen.
  4. Log in with username kali and password kali.

If it won’t boot with a VT-x / virtualization error: reboot into your PC’s BIOS/UEFI and enable Intel VT-x or AMD-V. It’s off by default on some machines and VMs can’t run without it.

04Update it once

The image was built a while ago. Bring it current so tools behave. Open the Terminal (the black icon in Kali’s top bar) and run:

$ sudo apt update && sudo apt full-upgrade -y

It asks for your password (kali) — the screen shows nothing as you type, that’s normal. Then it downloads and installs updates. Grab a coffee; this can take 10–20 minutes the first time.

05Take a snapshot — your undo button

This is the step beginners skip and regret. A snapshot freezes the machine’s exact state so you can return to it after any mess.

  1. In the Kali VM window’s menu bar, click Machine → Take Snapshot.
  2. Name it clean install and click OK.

Why it matters: break something, get a tool tangled, or want to redo a lab from zero — right-click the VM → Snapshots → Restore and you’re back to this exact moment in seconds. Take a fresh snapshot before each new lab.

06Confirm you’re ready

One command proves the tools are there. In the Kali terminal:

$ nmap --version

If it prints a version line (Nmap version 7.xx), everything works. That’s the tool you’ll use in the very next lab.

✓ Your lab is live

You have a safe, isolated Kali machine with a clean snapshot to fall back on. Every other StashGrid lab starts from right here.

If it didn’t work

  • The Kali window is black, tiny, or stuck at a blinking cursor. Usually the display settings. Power the VM off, then in VirtualBox Manager select it → Settings → Display, set Graphics Controller to VMSVGA and Video Memory to 128 MB, and start it again.
  • Everything crawls, or there is a green turtle icon in the VM’s status bar. On Windows that means Hyper-V (used by WSL2 and some security features) is running underneath VirtualBox. It still works, just slower. Give the VM more room first: Settings → System, 4096 MB memory and 2 processors.
  • apt update complains about a missing key or an invalid signature. Older Kali images ship an out-of-date archive key. Fetch the current one, then run the update again:
$ sudo wget https://archive.kali.org/archive-keyring.gpg -O /usr/share/keyrings/kali-archive-keyring.gpg
  • “Release file is not valid yet”. The VM’s clock is wrong. Shut it down fully (not just close the window), start it again, and give it a minute to sync the time before updating.

Your turn — no walkthrough

Prove the snapshot is real before you ever need it. Break something on purpose — delete a tool, rename a folder in your home directory, anything you would normally be afraid to touch — confirm it is broken, then get back to clean install and confirm nmap --version works again. No steps this time: you already have everything you need.

Keep the evidence. Start a plain notes file for your lab work and write the first entry: the date, your snapshot’s name, and one line on what you broke and how you recovered. Every later lab adds a line. That file becomes the most useful thing you own.

Clean up

Nothing to remove — this VM is the lab. Just shut it down properly when you are done (Machine → ACPI Shutdown, or sudo poweroff in the terminal) rather than closing the window mid-session.

Put it on your resume. Built a home security lab: a Kali Linux virtual machine in VirtualBox, isolated from the host, with snapshots for clean rollback. Change it to match what you actually did.

Tried it? Tell us

Nova built this lab from Steven’s ideas, and most StashGrid labs haven’t had a full run yet. If a step broke, behaved differently for you, or you know a better way, tell us. Ideas for the next lab are welcome too — no promises on timing.

Next

NextLab 01 — Your First Scan→

Original walkthrough. Download links go to the official VirtualBox, Kali and 7-Zip sites; steps reflect current standard setup — versions and screens change, so trust the official page if a button has moved.