fixup! Bug

Author: jfreden

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/security/authz/permission/IndicesPermission.java

@@ -694,6 +694,10 @@ private static boolean containsPrivilegeThatGrantsMappingUpdatesForBwc(Group gro
      * @return a list of tuples of all index and privilege pattern automaton
      */
     public List<Tuple<Automaton, Automaton>> indexGroupAutomatons(boolean combine) {
+        if (groups.length == 0) {
+            return List.of();
+        }
+
         List<Tuple<Automaton, Automaton>> allAutomatons = new ArrayList<>();
         allAutomatons.add(new Tuple<>(groups[0].getIndexMatcherAutomaton(), groups[0].privilege().getAutomaton()));