Index: /trunk/src/VBox/NetworkServices/NAT/pxping.c
===================================================================
--- /trunk/src/VBox/NetworkServices/NAT/pxping.c	(revision 50027)
+++ /trunk/src/VBox/NetworkServices/NAT/pxping.c	(revision 50028)
@@ -691,6 +691,8 @@
     if (!pcb->is_mapped) {
         if (hopl == 1) {
-            pbuf_header(p, iphlen); /* back to IP header */
-            icmp6_time_exceeded(p, ICMP6_TE_HL);
+            status = pbuf_header(p, iphlen); /* back to IP header */
+            if (RT_LIKELY(status == 0)) {
+                icmp6_time_exceeded(p, ICMP6_TE_HL);
+            }
             pbuf_free(p);
             return;