In this article I'll shed some light on how easy it is to perform a minor Drupal 8 upgrade between versions using free Putty SSH terminal and just a few lines of code. 

I assume your Drupal is configured under a VPS (take Linode, for example) and your installation path is /srv/www/

See: How to upgrade Drupal 6 to Drupal 7 - Process Upgrading Drupal 7 (minor upgrade)

Drupal security updates

Drupal security updates

By accessing available updates page (admin/reports/updates/update) we can easy update modules by just clicking update button, but if you are asked to update Drupal version a manual operation is asked

Update Drupal 8 core

Update Drupal 8 core

Now, open Putty, enter your username and password (make sure you login with root privileges). Make sure you change tourgeorgia.eu to your actual domain name

cd /srv/www/tourgeorgia.eu
sudo wget https://ftp.drupal.org/files/projects/drupal-8.3.2.tar.gz
sudo tar -xvzf drupal-8.3.2.tar.gz
sudo cp drupal-8.3.2/* public_html/ -R
sudo chown www-data:www-data public_html -R

Now visit /update.php page and make final updates. I there is no errors or issues displayed you should be fine and successfully updated your Drupal version to the latest.