diff --git a/lib/utils.js b/lib/utils.js
index 368070f611..e075f9e2ab 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -132,7 +132,7 @@ const isPlainObject = (val) => {
   }
 
   const prototype = getPrototypeOf(val);
-  return prototype === null || prototype === Object.prototype;
+  return (prototype === null || prototype === Object.prototype || Object.getPrototypeOf(prototype) === null) && !(Symbol.toStringTag in val) && !(Symbol.iterator in val);
 }
 
 /**