A5 - Security Misconfiguration
Description
Another one of the Rails security configurations relates to escaping HTML entities in JSON.
Bug

When the following setting is set to false, HTML entities in JSON response will not be encoded.

            <%= %q{
              ActiveSupport::escape_html_entities_in_json = false
            } %>

Solution

Edit the html_entities file at config/initializers/html_entities.rb and set the following to true.

            <%= %q{
              ActiveSupport::escape_html_entities_in_json = true
            } %>

Once the initializer is edited and the application is restarted, any HTML entities in JSON responses will be encoded.

Hint
Think HTML entities, escaping and initializers.