Index: /trunk/src/VBox/Devices/Network/SrvIntNetR0.cpp
===================================================================
--- /trunk/src/VBox/Devices/Network/SrvIntNetR0.cpp	(revision 54131)
+++ /trunk/src/VBox/Devices/Network/SrvIntNetR0.cpp	(revision 54132)
@@ -5186,5 +5186,6 @@
         if (intnetR0IsMacAddrMulticast(&pEthHdr->DstMac))
             enmSwDecision = INTNETSWDECISION_BROADCAST;
-        else if (pNetwork->fFlags & INTNET_OPEN_FLAGS_SHARED_MAC_ON_WIRE)
+        else if (   fSrc == INTNETTRUNKDIR_WIRE
+                 && (pNetwork->fFlags & INTNET_OPEN_FLAGS_SHARED_MAC_ON_WIRE))
             enmSwDecision = INTNETSWDECISION_BROADCAST;
         else