Find latest Rails stable version

I was using Facets today to find vulnerabilities in my Gemfile and 5 out of 6 are in the Rails gem.

I'm using Rails 4.0.0 and there seems to be a lot of vulnerabilities in this version so I head over to github/rails, click on branch >> 4-0-stable and locate the RAILS_VERSION file. At the time I'm writing this Rails is stable at 4.0.2.

To update Rails, you need to change its version in Gemfile:

gem 'rails', '4.0.2'

and

$ bundle update rails

in your command line. Don't forget to run your tests!