Virtualbox not seeing any usb devices in the usb filters settings

This may help you access the USB devices in your guest OS hosted in Ubuntu

First install dkms :

• sudo apt-get install dkms

Next install Gnome-System-Tools

• sudo apt-get install gnome-system-tools

Now launch the application - Users and Groups. If you're using unity you can do this by tapping the Super key and type user then click Users and Groups icon to start up the User Settings.

Click Manage Groups, find vboxusers, click properties, add your own user name and any other desired users to the vboxusers group. Click Ok.

Next you'll have to log out (sudo restart lightdm if you're using this DM) and back in. Now start VirtualBox and proceed with adding the USB devices.

This command will add your account to the vbox users group. It will allow your VirtualBox to detect USB flash drives.

sudo usermod -G vboxusers -a $USER

$USER value is your username. You can see it with echo $USER

$ whoami
foo
$ echo $USER
foo

You could also replace $USER by your Home username.

Then logout or reboot your computer and VirtualBox will now detect USB devices.

Sources :
Virtualbox Documentation on Ubuntu (French)
VirtualBox/USB - Community Help Wiki (English)

It should be enough to run

sudo gedit /etc/group

then find vboxusers line and add to it's end Yours user name.

After this reboot is suggested, but logging out or kill -9 -1 and logging in should be enough.