How to install usbserial and ftdi_sio modules to 14.04 Trusty Vagrant box?

I started a Vagrant box from https://cloud-images.ubuntu.com/vagrant/trusty/current/trusty-server-cloudimg-i386-vagrant-disk1.box. For some reason, this box does not seem to include usbserial and ftdi_sio modules by default. How to install them?

I have verified that modules are really missing with lsmod. Also modprobe usbserial throws modprobe: FATAL: Module usbserial not found. (as it does with ftdi_sio too).

The Linux kernel team decided to remove some modules from the base kernel to allow "virtual" images to be slimmed down. The extra modules are moved into linux-image-extra and you can get them installed by typing:

sudo apt-get install linux-image-extra-virtual