diff --git a/sys/dev/virtio/network/if_vtnet.c b/sys/dev/virtio/network/if_vtnet.c
--- a/sys/dev/virtio/network/if_vtnet.c
+++ b/sys/dev/virtio/network/if_vtnet.c
@@ -1302,9 +1302,13 @@
 
 	if ((ifp->if_flags ^ sc->vtnet_if_flags) &
 	    (IFF_PROMISC | IFF_ALLMULTI)) {
-		if ((sc->vtnet_flags & VTNET_FLAG_CTRL_RX) == 0)
-			return (ENOTSUP);
-		vtnet_rx_filter(sc);
+		if (sc->vtnet_flags & VTNET_FLAG_CTRL_RX)
+			vtnet_rx_filter(sc);
+		else {
+			if ((ifp->if_flags ^ sc->vtnet_if_flags) & IFF_ALLMULTI)
+				return (ENOTSUP);
+			ifp->if_flags |= IFF_PROMISC;
+		}
 	}
 
 out: