Our goal is to set-up a system such that, if you're not a logged-in administrator, you cannot:
- Install new applications
- Install browser extensions
- Change security-related settings
- Use Microsoft Edge or IE to access the internet (since these aren't/can't be locked down)
Optionally, we'll install a firewall for an added level of healthy paranoia to make sure that network calls aren’t being made by scripts or programmes that don't require administrator privileges. This can occasionally break things if not calibrated properly.
Also optionally, we'll set-up ClamAV as a secondary antivirus to catch whatever isn’t picked up by the built-in Windows Antivirus.
Step 1) Windows Get
Acquire an image of the Microsoft Windows installation disk in the way you normally might. Here's a handy link.
I just use an existing Windows install to create a USB install media using the Media Installation Tool at the above link, and follow the normal installation process.
Step 2) Install Windows / Create the Admin Account
Install Windows using the image you acquired in the previous step. We'll be setting up this computer with two users:
- An admin which we (or other technical folks) will use to set-up and perform maintenance on the device. I usually give this account the name "Admin".
- A user which will be used by the untechnical person. This account is not an administrator, and I usually give this account the name of the end-user.
When prompted for user information at installation, we'll set-up the admin account. The user account will be created once Windows is installed (in fact, in the next step).
Step 3) Create the User Account
Once installed, booted, and logged in:
- Enter the Windows 10 Settings panel (type "Settings" in the Start Menu).
- Click on "Accounts", and then "Family & other users" tab on the left.
- Click "Add someone else to this PC" (it has a plus on the left with it).
By default, the account is a "Standard User" (non-administrator), but you can check that by click on the new user's name in the "Family & other users" page and click on the "Change account type" to verify.
You may wish to check for and download Windows Updates at this time, as we'll be prompted to restart in Step 7.
Step 4) Install Firefox
Use Microsoft Edge for the only thing it's good for; installing Firefox.
Step 5) Set-Up Non-Administrator Group Policy
We'll use Microsoft Window's Group Policy to apply rules and restrictions for non-administrator users.
Follow the steps in this TenForums tutorial and save the shortcut in the last step to the Desktop (we'll use it again later).
Step 6) Add Group Policy Rules for Microsoft Edge
Use the shortcut from the previous step to create non-administrator rules for Microsoft Edge. Use the Tree on the left to navigate to Console Root\Local Computer\Non-Administrators Policy\User Configuration\Administrative Templates\Windows Components\Microsoft Edge
.
Change the following settings to lock-down Microsoft Edge:
Allow Developer Tools
toDisabled
Allow Extensions
toDisabled
Allow Adobe Flash
toDisabled
Allow search engine customization
toDisabled
Allow Sidelaoding of extension
toDisabled
Configure Windows Defender SmartScreen
toEnabled
Allow web content on New Tab page
toDisabled
(this is the most important)Prevent bypassing Windows Defender SmartScreen prompts for sites
toEnabled
Prevent bypassing Windows Defender SmartScreen prompts for files
toEnabled
Then, navigate to Console Root\Local Computer\Non-Administrators Policy\User Configuration\Administrative Templates\System
.
Then change the key Don't run specified Windows applications
to Enabled
, click the "Show…" button with the "List of disallowed applications" label. In that window write msedge.exe
as one of the entries.
Step 7) Add Group Policy Rules for Internet Explorer
In the same Window as before, use the Tree on the left to navigate to Console Root\Local Computer\Non-Administrators Policy\User Configuration\Administrative Templates\Windows Components\Internet Explorer
In the Security Page\Internet Zone
page change the following settings:
Turn on Protected Mode
toEnabled
Show security warning for potentially unsafe files
toEnabled
Allow file downloads
toDisabled
Allow font downloads
toDisabled
Java permissions
toEnabled
and set the Java permissions dropdown toDisable Java
Launching applications and files in an IFRAME
toDisabled
Then search "Turn Window features on and off", click it, and uncheck "Internet Explorer 11". You'll then get prompted to restart your computer, which you may do.
Step 8) Add Mozilla Firefox Policy Definitions
Download the Mozilla Firefox Policy Definitions from GitHub. Copy the *.adml
files in the root of the repo to C:\Windows\PolicyDefinitions
and the *.adml
files in the en-us
folder (or your locale) in the folder C:\Windows\PolicyDefinitions\en-us
.
Step 9) Install Desired Firefox Add-ons on the User Account
Log-in to the Standard User account the untechnical user is meant to use. Then install the add-ons you desire, since we’ll be disabling this later. You can enable again later if you change your mind, so don't worry.
I recommend the following extensions to prevent users from putting themselves at risk:
- uBlock Origin
- Privacy Badger
- HTTPS Everywhere
Step 10) Add Group Policy Rules for Firefox
Open up the Group Policy shortcut we saved to the desktop and go to Console Root\Local Computer\Non-Administrators Policy\User Configuration\Administrative Templates\Mozilla\Firefox
.
Set the following keys:
Application Autoupdate
toEnabled
Block Add-ons Manager
toEnabled
Block about:config
toEnabled
Block about:profiles
toEnabled
Disable Developer Tools
toEnabled
Go to the child folder Addons
in the Firefox
folder we navigated to with the path above.
Set the following keys:
Allow add-on installs from websites
toDisabled
Go to the child folder Flash
in the Firefox
folder we navigate to with earlier.
Set the following keys:
Activate Flash on websites
toDisabled
If your user doesn’t plan on using in-browser video conferencing, you can block Camera and Microphone access.
Go to the child folder Permissions/Camera
:
Block new requests asking to access the camera
toEnabled
Go to the child folder Permissions/Microphone
:
Block new requests asking to access the microphone
toEnabled
Go to the child folder Search
and set the following keys:
Prevent Search Engine Installs
toEnabled
Go to the child folder Tracking Protection
and set the following keys:
Enabled
toEnabled
Cryptomining
toEnabled
Do not allow tracking protection preferences to be changed
toEnabled
Go to the child folder User Messaging
and set the following keys:
Extensions Recommendations
toDisabled