We still provide security for Elasticsearch 2, 5 and 6
Search Guard has been providing Enterprise security for Elasticsearch since Version 2. Search guard still provides versions of our Security plugins for Elasticsearch 6 as well as version 5 and, yes, even version 2. By implementing Search Guard you can stabilize your security particularly with Encryption in motion, Authn and Authz. We can also provide guidance on how to migrate to more current versions of Elasticsearch (Paid service).