--- a/jdk/src/share/classes/java/io/ObjectInputStream.java	Wed Nov 07 14:26:41 2012 +0000
+++ b/jdk/src/share/classes/java/io/ObjectInputStream.java	Thu Nov 08 15:41:01 2012 -0800
@@ -1752,6 +1752,12 @@
         ObjectStreamClass desc = readClassDesc(false);
         desc.checkDeserialize();
 
+        Class<?> cl = desc.forClass();
+        if (cl == String.class || cl == Class.class
+                || cl == ObjectStreamClass.class) {
+            throw new InvalidClassException("invalid class descriptor");
+        }
+
         Object obj;
         try {
             obj = desc.isInstantiable() ? desc.newInstance() : null;