Search Guard

Search Guard is an Open Source security suite for Elasticsearch and the entire ELK stack that offers encryption, authentication, authorization, audit logging and multi tenancy. Whether you just want to encrypt data in transit, authenticate users against Active Directory, use Kerberos or JSON web tokens for Single Sign On or need to monitor and log malicious access attempts, Search Guard is your one-stop solution. And the best part is that the Community edition comes for free!
Source: https://www.linkedin.com/company/search-guard/about/