/usr/lib/ruby/vendor_ruby/ is in ruby-simple-navigation 4.0.3-1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/vendor_ruby/simple_navigation.rb
/usr/lib/ruby/vendor_ruby/simple-navigation.rb
/usr/lib/ruby/vendor_ruby/generators/
/usr/lib/ruby/vendor_ruby/generators/navigation_config/
/usr/lib/ruby/vendor_ruby/generators/navigation_config/navigation_config_generator.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/
/usr/lib/ruby/vendor_ruby/simple_navigation/configuration.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/renderer/
/usr/lib/ruby/vendor_ruby/simple_navigation/renderer/breadcrumbs.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/renderer/text.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/renderer/json.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/renderer/links.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/renderer/list.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/renderer/base.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/adapters/
/usr/lib/ruby/vendor_ruby/simple_navigation/adapters/padrino.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/adapters/sinatra.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/adapters/nanoc.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/adapters/base.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/adapters/rails.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/config_file_finder.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/adapters.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/item.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/item_adapter.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/items_provider.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/helpers.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/version.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/config_file.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/renderer.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/item_container.rb
/usr/lib/ruby/vendor_ruby/simple_navigation/railtie.rb