Index: /trunk/src/VBox/Main/src-server/HostDnsService.cpp
===================================================================
--- /trunk/src/VBox/Main/src-server/HostDnsService.cpp	(revision 79794)
+++ /trunk/src/VBox/Main/src-server/HostDnsService.cpp	(revision 79795)
@@ -83,4 +83,6 @@
         : pProxy(NULL)
         , fThreaded(aThreaded)
+        , hMonitorThreadEvent(NIL_RTSEMEVENT)
+        , hMonitorThread(NIL_RTTHREAD)
     {}
 
@@ -198,4 +200,10 @@
         if (RT_FAILURE(rc))
             LogRel(("HostDnsMonitor: waiting for thread failed with rc=%Rrc\n", rc));
+
+        if (m->hMonitorThreadEvent != NIL_RTSEMEVENT)
+        {
+            RTSemEventDestroy(m->hMonitorThreadEvent);
+            m->hMonitorThreadEvent = NIL_RTSEMEVENT;
+        }
     }