/usr/lib/ruby/vendor_ruby/merb-core/dispatch/ is in ruby-merb-core 1.1.3+dfsg-2.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/cookies.rb
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/default_exception/
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/default_exception/default_exception.rb
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/default_exception/views/
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/default_exception/views/_css.html.erb
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/default_exception/views/_javascript.html.erb
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/default_exception/views/index.html.erb
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/dispatcher.rb
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/request.rb
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/request_parsers.rb
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/router/
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/router.rb
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/router/behavior.rb
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/router/cached_proc.rb
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/router/resources.rb
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/router/route.rb
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/session/
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/session.rb
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/session/container.rb
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/session/cookie.rb
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/session/memcached.rb
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/session/memory.rb
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/session/store_container.rb
/usr/lib/ruby/vendor_ruby/merb-core/dispatch/worker.rb