Have you ever used your shared connection on your smartphone and used a VPN on it, and thought that the rest of your devices were protected? Well no, and let's see why.
As we well know, or should, a VPN largely protects our connection. Many organizations use this type of connection for remote work and access to center services.
In addition, on a personal level, it also protects us from possible attack vectors, anonymizes our connection, allows us to change our geolocation... among other things.
Well, as I mentioned in an entry on my Linkedin profile, it was necessary for me to create a Hotspot from my smartphone, in which I used a VPN, to connect to other devices, such as my tablet or laptop. And what was my surprise, that the rest of the devices are not protected by the VPN.
What is this about?
Mainly because the most common VPN services that we hire, whether free or not, are based on the installation of a client on each host, encrypting the connection on this device, since that program or app is the one that has those keys. by which communications are encrypted. A solution to this problem is to install the client software on as many devices as we need.
This may not be possible, whether due to price, type of VPN we need, type of corporate VPN that has been provided to us...
So can the provided VPN connection be shared?
In principle and the short answer is no. But there are different ways.
1.- A VPN installed on our router or firewall.
2.- Create a shared connection and configure it from Windows (we will do an example later)
3.- On Android smartphones, it is necessary to be root, and through several apps.
Explanation of each point.
1.- Enter the router configuration, in the VPN section, if it has one, it is configured according to the data provided by the contracted client or provided by the organization. It is a very brief explanation, but since there is so much diversity in connections and devices, it is very difficult to make an exact guide. But, organizations or clients usually provide it.
2.- Connect your computer to the Internet through a VPN connection. This can be done through a VPN connection established on your computer or by using a virtual network adapter (such as OpenVPN) to connect to a VPN server.
Open Control Panel on your computer and select "Network and Internet" and then "Network and Sharing Center."
In the left side panel, click “Change adapter settings.”
In the window that opens, find the VPN connection you are using to connect to the Internet and right-click on it. Select “Properties” from the drop-down menu.
In the VPN connection properties window, go to the “Sharing” tab.
Check the box that says "Allow other network users to connect through this computer's Internet connection."
From the “Home Virtual Private Network” drop-down menu, select the network connection you want to share with other devices (for example, Ethernet or Wi-Fi).
Click "OK" to save the changes.
3.-
Install “VPN Hotspot – Wi-Fi tethering repeater” from Google Play Store
Install Magisk Manager and SuperSU apps on an Android device
Launch the VPN Hotspot app to start the setup process.
There will be a screen popup for superuser grant which means root permission
Press the Mobile Data and Wi-Fi button to toggle them “On”.
After that, activate the Hotspot option from the Android device
Click on the downloaded app “VPN Hotspot – Wi-Fi tethering repeater”
Enable Wi-Fi hotspot to create “swlan0” and activate “VPN Hotspot”
Connect the necessary device with an Android Wi-Fi connection via the hotspot feature!
Conclusion.
In something that seems like we are safe by default, it has happened to me, we are, without wanting to pretend, to have a large attack vector, thinking that we were safe.
You never stop learning, and with this I hope you have become aware of the ways you can enjoy a secure VPN connection, either by having a client on each device, or by sharing that connection as explained.
Greetings, see you next time.
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