/usr/lib/ruby/vendor_ruby/ is in ruby-ethon 0.9.0-1ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/vendor_ruby/ethon/
/usr/lib/ruby/vendor_ruby/ethon/easy/http/
/usr/lib/ruby/vendor_ruby/ethon/curl.rb
/usr/lib/ruby/vendor_ruby/ethon/curls/
/usr/lib/ruby/vendor_ruby/ethon/curls/classes.rb
/usr/lib/ruby/vendor_ruby/ethon/curls/codes.rb
/usr/lib/ruby/vendor_ruby/ethon/curls/constants.rb
/usr/lib/ruby/vendor_ruby/ethon/curls/form_options.rb
/usr/lib/ruby/vendor_ruby/ethon/curls/functions.rb
/usr/lib/ruby/vendor_ruby/ethon/curls/infos.rb
/usr/lib/ruby/vendor_ruby/ethon/curls/messages.rb
/usr/lib/ruby/vendor_ruby/ethon/curls/options.rb
/usr/lib/ruby/vendor_ruby/ethon/curls/settings.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/
/usr/lib/ruby/vendor_ruby/ethon/easy/callbacks.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/debug_info.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/features.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/form.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/header.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/http/actionable.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/http/custom.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/http/delete.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/http/get.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/http/head.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/http/options.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/http/patch.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/http/post.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/http/postable.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/http/put.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/http/putable.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/http.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/informations.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/mirror.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/operations.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/options.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/params.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/queryable.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/response_callbacks.rb
/usr/lib/ruby/vendor_ruby/ethon/easy/util.rb
/usr/lib/ruby/vendor_ruby/ethon/easy.rb
/usr/lib/ruby/vendor_ruby/ethon/errors/
/usr/lib/ruby/vendor_ruby/ethon/errors/ethon_error.rb
/usr/lib/ruby/vendor_ruby/ethon/errors/global_init.rb
/usr/lib/ruby/vendor_ruby/ethon/errors/invalid_option.rb
/usr/lib/ruby/vendor_ruby/ethon/errors/invalid_value.rb
/usr/lib/ruby/vendor_ruby/ethon/errors/multi_add.rb
/usr/lib/ruby/vendor_ruby/ethon/errors/multi_fdset.rb
/usr/lib/ruby/vendor_ruby/ethon/errors/multi_remove.rb
/usr/lib/ruby/vendor_ruby/ethon/errors/multi_timeout.rb
/usr/lib/ruby/vendor_ruby/ethon/errors/select.rb
/usr/lib/ruby/vendor_ruby/ethon/errors.rb
/usr/lib/ruby/vendor_ruby/ethon/libc.rb
/usr/lib/ruby/vendor_ruby/ethon/loggable.rb
/usr/lib/ruby/vendor_ruby/ethon/multi/
/usr/lib/ruby/vendor_ruby/ethon/multi/operations.rb
/usr/lib/ruby/vendor_ruby/ethon/multi/options.rb
/usr/lib/ruby/vendor_ruby/ethon/multi/stack.rb
/usr/lib/ruby/vendor_ruby/ethon/multi.rb
/usr/lib/ruby/vendor_ruby/ethon/version.rb
/usr/lib/ruby/vendor_ruby/ethon.rb