Securing Kubernetes With Ease

Let there be light and then there was light - That is kind of what is happening in the world of DevOps today. Where there was darkness, now there is light! The constant effort to automate, optimize and make tasks easier have helped teams in many an enterprise to focus their efforts and build workflows that bring unparalleled efficiency to their teams. In the not so distant past application development and management were once done with the help of Virtual Machines or VMs as we call it. The new standard that has been set in this area is containerization. Containerization is an OS-level virtualization technique that is useful in running, deploying and managing applications with or without the usage of virtual machines. What gives containerization an edge is that this method doesn't demand the launching of the whole VM for an application. Why is this important? “Density” of applications hosted on the same hardware is increased - a.k.a more bang for your buck! 

Agility, cloud adoption, their ability to integrate with other IT processes and more, made containers, even more, developer-friendly. Most of the organizations that handle large application production environments depend upon various container orchestration platforms. Kubernetes is the first name that pops up on this list. In this article we will discuss Kubernetes and highlight some of the security features that help teams secure their workloads and some gotchas that they can sidestep easily.

What is Kubernetes?

Kubernetes or K8 is the primary choice of most people who are into containerization. This open source containerization platform which was introduced by Google, deals with the management and deployment of containerized applications in an automated manner. Kubernetes eased the way of managing containerized apps in large computer clusters. It provides several features such as the provisioning of container and storage interfaces, networking facilities, API primitives, built-in security measures, multiple deployment options and more. One of the best things Kubernetes offers you is a couple of effective security policies for the clusters. Let’s go through an overview of the various high-level Kubernetes security policies and processes below.

Secrets API

Secrets is a Kubernetes object which can be used to save sensitive information such as passwords, keys, and other tokens in a secure way. Saving such data in secrets will let you know about its usage and also ensures the avoidance of accidental exposure. Secrets will be mostly small text documents in which you can save your sensitive data. A secrets can be created in Kubernetes using either a text file or a yaml file. These secrets objects created are independent of the Kubernetes pods and hence the risk of exposure is pretty low during the time of creating, viewing or editing pods. Unless a pod requires a secrets object, it won’t be sent to it. Also, after a pod is done with the associated secrets object, the Kubelet (Kubelet run pods in Kubernetes) will delete the object’s local copy. The communications from user to API servers and back are secured using SSL/TLS cryptographic protocols. Secrets will get extra security when they’re transmitted over this channel whenever a container requires them.

Pod Security Policies

Kubernetes comes with Pod Security Policies which is a cluster-level resource that ensures the security of the pod in all aspects. This pod security policy is a Kubernetes object which defines a set of rules that must be followed by pods to get accepted into the system while running. With the use of the pod security policy object, an administrator can restrict the creation and updating of a pod and can also be used to set default values for many fields. Just creating a pod security policy will do zero good. To make use of its features, the service account of the target pod, i.e., the user requesting the same must be authorized to use the policy. Using the word ‘verb’ in the policy, this can be enabled. In short, these pod security policy objects enable pod to pod access rules and helps to manage various pod privileges.

Role-Based Access Control (RBAC) System

Using the built-in role-based access control mechanism, you can configure how a user or a group of users can access or interact with any Kubernetes object in your cluster. You can create either a cluster role or Cluster role binding objects to define and assign permissions in Kubernetes. Cluster role objects define the set of resource types and operations that can be assigned to any user or a group of users. But these types of objects do not specify the user or a group of users. Cluster Role Binding objects assigns a cluster role or cluster to a user or a group of users.

Network Policies

Kubernetes network policies define how a pod or group of pods can communicate with each other or to a network endpoint. Usually, by default, pods in Kubernetes will be in a non-isolated nature and they’ll accept traffic from any sources. Once a network policy is set, the pods will be in an isolated state. This means that the pods will never accept any traffic from any sources that is against the imposed network policy. Just by creating a network policy won’t benefit you in any way. You should enable network plugins and a working network solution for that.

The other side of the coin

Life is not all roses and honey, so, let’s now think about the hurdles on the way. What if the security of the Kubernetes host itself is somehow breached? What if someone got root access to the Kubernetes containers? To avoid such security risks, what should be done? The answer is simple. Privileged Access Management (PAM). One of the many issues that confound security teams who need to bless workflows that use Kubernetes is to keep the users away from accessing the Kubernetes host and every other resources that are not meant to be accessed by them. A secure PAM solution for your Kubernetes host account will keep the outsiders and unauthorized insiders away. PAM solutions can be used for setting secured and least-privilege access along with the adoption of efficient security measures to accounts will make the Kubernetes journey safer.

What does it mean to have a PAM solution for Kubernetes?

Most cybercriminals on the internet aim their efforts at privileged accounts as they can steal the credential of the same, misuse it and harm the enterprise. Hence such accounts demand more protection. Users or outsiders can’t access anything in Kubernetes without your knowledge if you’re using a Privileged Access Management tool. You’re the master. You will decide and the tools will act. You can let the PAM security measures do its job independently and still easily audit and log entries of your Kubernetes account. You can also potentially remove or block entries in a flexible way.

Wonder the security provided to your Kubernetes resources is strong enough to stop accidental or focused breaches? What if someone unauthorized accessed any of your Kubernetes resources? To avoid this, use any of the Multi-Factor Authentication techniques to control strict and authorized accessibility to Kubernetes. Only users who are verified successfully by these authentication techniques will be allowed to access the required resources. There are numerous ways to restrict access to any of the resources or accounts ranging from setting up strong passwords to using various biometric measures for accessing them.

PAM solution features such as password rotation and realtime recording make audit and compliance reporting simple. The level of being pedantic is tunable for most PAM products - you can monitor every command made by a user in Kubernetes and you can easily detect and correct if at all you notice something fishy. This means you can keep a close watch on who is accessing what in Kubernetes. Also, Lightweight Directory Access Protocol or LDAP is an open source tool and also a cross-platform protocol used for directory service authentications. Microsoft AD or Active Directory is a directory services implementation that provides you a couple of effective functionalities such as user authentication, user and group access management, policy administration, etc. Linking the Kubernetes access to LDAP and Active Directory will make the picture of security even bigger and stronger. PAM tolls make this process rather simple and enterprises benefit from having one source of truth.

Conclusion

Kubernetes makes things easy being a container orchestration platform with some of the effective security measures built into the system. PAM makes it easy for Kubernetes to go many steps further by protecting it top to bottom from misuse, unauthorized usage and data breaches. In short, if you want to grab all the above mentioned features and set up a super-secure protection to Kubernetes host, accounts and resources in one go, the answer you seek is PAM. Onion Id’s PAM solutions are effective and causes zero downtime while deploying it because of its easy and automated management features. If you do require any additional clarifications, please feel free to get in touch with us at https://www.onionid.com or in case you need information about a complete, lightweight, cost-effective PAM solution with great after-sales support, please connect with us at [email protected].