diff --git a/epan/dissectors/packet-cipsafety.c b/epan/dissectors/packet-cipsafety.c
index 233e6b5161..6156decb7d 100644
--- a/epan/dissectors/packet-cipsafety.c
+++ b/epan/dissectors/packet-cipsafety.c
@@ -1511,6 +1511,11 @@ dissect_cip_safety_data( proto_tree *tree, proto_item *item, tvbuff_t *tvb, int
    /* compute the base packet length to determine what is actual I/O data */
    base_length = multicast ? 12 : 6;
 
+   if (item_length <= base_length) {
+      expert_add_info(pinfo, item, &ei_mal_io);
+      return;
+   }
+
    if (((conn_type == ECIDT_O2T) && (server_dir == FALSE)) ||
        ((conn_type == ECIDT_T2O) && (server_dir == TRUE)))
    {