--- old/src/hotspot/share/prims/jniCheck.cpp	2018-01-02 18:27:22.593218296 -0500
+++ new/src/hotspot/share/prims/jniCheck.cpp	2018-01-02 18:27:22.261201163 -0500
@@ -1930,6 +1930,13 @@
   checked_jni_DeleteWeakGlobalRef(JNIEnv *env,
                                   jweak ref))
     functionEnterExceptionAllowed(thr);
+    IN_VM(
+      jniCheck::validate_object(thr, ref);
+      if (ref && !JNIHandles::is_weak_global_handle(ref)) {
+        ReportJNIFatalError(thr,
+             "Invalid weak global JNI handle passed to DeleteWeakGlobalRef");
+      }
+    )
     UNCHECKED()->DeleteWeakGlobalRef(env, ref);
     functionExit(thr);
 JNI_END