Use Kingo to root your android device via VirtualBox with a free Windows image. Just make sure to install the VirtualBox extension pack and enable USB 2.0 support. This may very well work on Linux as well.
Kingo Root seems to be the easiest way to root most modern Android devices. I was excited to use it on my Samsung Galaxy Note 3, but dismayed when I discovered it only works on Windows. I've never booted Windows on my MacBook, and I really didn't want to set up a Boot Camp partition just to root my phone, so I set out to figure out whether I could get Kingo to work inside of a free virtual machine.
VirtualBox is a great free virtualization tool that will allow you to run one operating system in a window inside of another. For example, you can run Windows inside of MacOS, which is what we're going to do in this case. Download and install VirtualBox and the Extension Pack (located right below the download links on the rather poorly designed downloads page). That was easy.
Get a Windows virtual machine image
Next, you need to install Windows. The ievms project provides pre-built VirtualBox images for rapid testing of various versions of Internet Explorer, which is useful for web developers like me. It also provides the quickest way that I found to boot Windows inside of VirtualBox without going through the painful Windows installation wizard. By default, it will install several different versions of Windows (each with different versions of Internet Explorer) totaling tens of gigabytes. You really only need one of these, so I decided to go with Windows XP SP3 since it was one of the smallest options.
curl -s https://raw.githubusercontent.com/xdissent/ievms/master/ievms.sh | env IEVMS_VERSIONS="8" bash
Configure the Virtual Machine
You'll need to set some options for the virtual machine to make sure it plays nice with your device's USB connection. Shut down the Windows VM if it's running and go into its settings. Now is the time to install that Extension Pack if you haven't already. Enable the USB 2.0 controller, and with your device connected, add it to the USB Device Filters list (this will give VirtualBox exclusive access to the device when it is running).
Start up the Windows virtual machine and install Kingo Root inside of it. It should install the drivers for your device automatically and let you root it with one click. If you see a message like "Connection Unstabitil" [sic] or something to that effect, then you either didn't install the VirtualBox Extension Pack & enable USB 2.0, or you're using a USB 3.0 cable (the one with the wide connector that comes with the Galaxy Note 3 and possibly other newer devices). Make sure to use standard MicroUSB cable and you should be good to go.
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