/usr/ is in ruby-rack-rewrite 1.5.1-1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/
/usr/share/rubygems-integration/
/usr/share/rubygems-integration/all/
/usr/share/rubygems-integration/all/specifications/
/usr/share/rubygems-integration/all/specifications/rack-rewrite-1.5.1.gemspec
/usr/share/doc/
/usr/share/doc/ruby-rack-rewrite/
/usr/share/doc/ruby-rack-rewrite/copyright
/usr/share/doc/ruby-rack-rewrite/changelog.Debian.gz
/usr/lib/
/usr/lib/ruby/
/usr/lib/ruby/vendor_ruby/
/usr/lib/ruby/vendor_ruby/rack/
/usr/lib/ruby/vendor_ruby/rack/rewrite.rb
/usr/lib/ruby/vendor_ruby/rack/rewrite/
/usr/lib/ruby/vendor_ruby/rack/rewrite/rule.rb
/usr/lib/ruby/vendor_ruby/rack/rewrite/version.rb
/usr/lib/ruby/vendor_ruby/rack-rewrite.rb