/usr/lib/ruby/vendor_ruby/rails/generators/rails/app/templates/config/initializers/ is in ruby-railties 2:4.2.6-1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/vendor_ruby/rails/generators/rails/app/templates/config/initializers/assets.rb.tt
/usr/lib/ruby/vendor_ruby/rails/generators/rails/app/templates/config/initializers/backtrace_silencers.rb
/usr/lib/ruby/vendor_ruby/rails/generators/rails/app/templates/config/initializers/cookies_serializer.rb
/usr/lib/ruby/vendor_ruby/rails/generators/rails/app/templates/config/initializers/filter_parameter_logging.rb
/usr/lib/ruby/vendor_ruby/rails/generators/rails/app/templates/config/initializers/inflections.rb
/usr/lib/ruby/vendor_ruby/rails/generators/rails/app/templates/config/initializers/mime_types.rb
/usr/lib/ruby/vendor_ruby/rails/generators/rails/app/templates/config/initializers/session_store.rb.tt
/usr/lib/ruby/vendor_ruby/rails/generators/rails/app/templates/config/initializers/wrap_parameters.rb.tt