diff --git a/_baseSet.js b/_baseSet.js
index 99f4fbf9c347a74594f975df62ee353d06c85c55..316f9e8b537e294230c5123789c224c41a7034e8 100644
--- a/_baseSet.js
+++ b/_baseSet.js
@@ -37,7 +37,7 @@ function baseSet(object, path, value, customizer) {
       var objValue = nested[key];
       newValue = customizer ? customizer(objValue, key, nested) : undefined;
       if (newValue === undefined) {
-        newValue = isObject(objValue)
+        newValue = isObject(objValue) && Object.prototype.hasOwnProperty.call(nested, key)
           ? objValue
           : (isIndex(path[index + 1]) ? [] : {});
       }
diff --git a/lodash.js b/lodash.js
index 902bfd4ee8f96898526f4776b061ce1d1c189ecc..c45042ae7e99ea0b900eb665989bcb72bf880b0f 100644
--- a/lodash.js
+++ b/lodash.js
@@ -4045,7 +4045,7 @@
           var objValue = nested[key];
           newValue = customizer ? customizer(objValue, key, nested) : undefined;
           if (newValue === undefined) {
-            newValue = isObject(objValue)
+            newValue = isObject(objValue) && Object.prototype.hasOwnProperty.call(nested, key)
               ? objValue
               : (isIndex(path[index + 1]) ? [] : {});
           }