diff --git a/lib/bson/hash.rb b/lib/bson/hash.rb
index 197349cc5..4bd7adf29 100644
--- a/lib/bson/hash.rb
+++ b/lib/bson/hash.rb
@@ -167,7 +167,7 @@ def maybe_dbref(hash)
       #
       # @return [ Hash ] the hash parsed from the buffer
       def parse_hash_from_buffer(buffer, **options)
-        hash = Document.allocate
+        hash = ruby_base_type.allocate
         start_position = buffer.read_position
         expected_byte_size = buffer.get_int32
 
@@ -200,6 +200,10 @@ def parse_hash_contents(hash, buffer, **options)
           hash.store(field, value)
         end
       end
+
+      def ruby_base_type
+        BSON::Registry.get(BSON_TYPE)
+      end
     end
 
     # Register this type when the module is loaded.
diff --git a/lib/bson/registry.rb b/lib/bson/registry.rb
index 047df9a5b..beb25cdb8 100644
--- a/lib/bson/registry.rb
+++ b/lib/bson/registry.rb
@@ -42,7 +42,7 @@ module Registry
     #
     # @since 2.0.0
     def get(byte, field = nil)
-      if type = MAPPINGS[byte] || (byte.is_a?(String) && type = MAPPINGS[byte.ord])
+      if (type = MAPPINGS[byte]) || (byte.is_a?(String) && (type = MAPPINGS[byte.ord]))
         type
       else
         handle_unsupported_type!(byte, field)