/usr/lib/ruby/vendor_ruby/log4r/outputter/ is in ruby-log4r 1.1.10-3.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/vendor_ruby/log4r/outputter/consoleoutputters.rb
/usr/lib/ruby/vendor_ruby/log4r/outputter/datefileoutputter.rb
/usr/lib/ruby/vendor_ruby/log4r/outputter/emailoutputter.rb
/usr/lib/ruby/vendor_ruby/log4r/outputter/fileoutputter.rb
/usr/lib/ruby/vendor_ruby/log4r/outputter/iooutputter.rb
/usr/lib/ruby/vendor_ruby/log4r/outputter/outputter.rb
/usr/lib/ruby/vendor_ruby/log4r/outputter/outputterfactory.rb
/usr/lib/ruby/vendor_ruby/log4r/outputter/remoteoutputter.rb
/usr/lib/ruby/vendor_ruby/log4r/outputter/rollingfileoutputter.rb
/usr/lib/ruby/vendor_ruby/log4r/outputter/scribeoutputter.rb
/usr/lib/ruby/vendor_ruby/log4r/outputter/staticoutputter.rb
/usr/lib/ruby/vendor_ruby/log4r/outputter/syslogoutputter.rb
/usr/lib/ruby/vendor_ruby/log4r/outputter/udpoutputter.rb