Amid a growing number of increasingly sophisticated cyber attacks, enterprises are searching for ways to enable security wherever possible, in order to protect their data in transit and at rest. Big data processing is no exception; security is a very broad topic and to cover it in its entirety would be beyond the scope of this post. Instead, we will focus exclusively on those security capabilities that Spark on Kubernetes provides (by Spark on Kubernetes, we mean when Spark uses Kubernetes as an external cluster manager for creating and running executors).