/usr/lib/ruby/vendor_ruby/ is in ruby-rqrcode 0.3.3-2.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/vendor_ruby/rqrcode/
/usr/lib/ruby/vendor_ruby/rqrcode/core_ext/
/usr/lib/ruby/vendor_ruby/rqrcode/core_ext/array/
/usr/lib/ruby/vendor_ruby/rqrcode/core_ext/array/behavior.rb
/usr/lib/ruby/vendor_ruby/rqrcode/core_ext/array.rb
/usr/lib/ruby/vendor_ruby/rqrcode/core_ext/integer.rb
/usr/lib/ruby/vendor_ruby/rqrcode/core_ext/integer/
/usr/lib/ruby/vendor_ruby/rqrcode/core_ext/integer/bitwise.rb
/usr/lib/ruby/vendor_ruby/rqrcode/qrcode/
/usr/lib/ruby/vendor_ruby/rqrcode/qrcode/qr_util.rb
/usr/lib/ruby/vendor_ruby/rqrcode/qrcode/qr_polynomial.rb
/usr/lib/ruby/vendor_ruby/rqrcode/qrcode/qr_8bit_byte.rb
/usr/lib/ruby/vendor_ruby/rqrcode/qrcode/qr_rs_block.rb
/usr/lib/ruby/vendor_ruby/rqrcode/qrcode/qr_code.rb
/usr/lib/ruby/vendor_ruby/rqrcode/qrcode/qr_math.rb
/usr/lib/ruby/vendor_ruby/rqrcode/qrcode/qr_bit_buffer.rb
/usr/lib/ruby/vendor_ruby/rqrcode/qrcode.rb
/usr/lib/ruby/vendor_ruby/rqrcode/core_ext.rb
/usr/lib/ruby/vendor_ruby/rqrcode.rb