What is Kubernetes Security?
Security is a critical component for any company creating and running software applications. If you use Kubernetes technology to run containerized applications, then you must provide complete security to protect the data within the containers. Safeguarding your data can be achieved by many methods and practices. Kubernetes security has come into play for the automatic deployment, scaling, and management of applications that are run in containers.
With Kubernetes, you will be able to manage large-scale containers running in any environment which might not be possible if you carry out the task manually. If you do not have any proper measures from the security perspective, you might have gaping holes within your Kubernetes security.
In this article, we will deep dive into the Kubernetes security, risks, challenges, and security checklist for Kubernetes.
What is Kubernetes Security?
Kubernetes security is an open-source system that allows you to automate the process for deploying, scaling, and maintaining the containers running applications. It provides an easier way for managing, securing, and discovering the containers that are grouped in some logical units. Being a leading container orchestration tool, Kubernetes ensures the complete safety of your system. It requires you to understand your system completely to check upon the occurring vulnerabilities while you create, deploy, or run applications using Kubernetes.
Using Kubernetes security, you can address the native security within the cloud, your application, container, and even your code. By doing so, it ensures all the systems and processes are in the right place to ensure physical security efficiently. It follows the intelligent container design standards, access control management, for ensuring cluster and application security. It allows you to check build-time for vulnerabilities, code encryption, and securing unused ports in a production system.
What are the associated risks and challenges?
Kubernetes offers various security advantages but still comes with many challenges, making it prone to some security vulnerabilities.
- Greater attack surface– your system might create and run thousands of containers on any platform. Using containers you will be able to take benefits of the microservice architecture and can operate faster and efficiently. This might create a security blind spot that will make your system more vulnerable for various attacks. If you keep on deploying more containers on your system, it might be difficult for you to manage them.
- Misuse of registries and images– make sure your images and registries are secure wherever you store them on the system. Try to scan them regularly for any vulnerabilities. If you fail to do so, your application and system can be misused across the network.
- Network effects– The containers are bound to communicate with other containers running within the network. This increased the chances of spreading the container security breach across the network. The spread depends on how one container is connected to other containers.
- Compliance challenges– most of the standard policies of any organization were not created for the cloud native environment running containers. So, businesses should try to automate the process of auditing and monitoring for successful scaling.
If you have successfully addressed such situations and challenges then there are very less chances of any security threat to your system.
Best practices of a container
Here, we have provided a detailed outline of container best practices that can be followed at the three different stages of the container lifecycle.
1. Build phase of a container
You should prioritize securing container images before working on any other security measures if you want to prevent it from going on to the next stage. The most common practice is to use images that have a minimal base and are free from OS package managers. Your system may be vulnerable if you use an OS package manager. You can also avoid adding unnecessary components and always use the most recent images.
You should also carry out a regular scan of all images as a part of ensuring Kubernetes security. Use an appropriate tool to efficiently scan the images, OS package, and runtime for all possible vulnerabilities. CI/CD pipelines can be integrated into these checks to provide better and more accurate results.
Make sure you fix the vulnerability before moving the container or code to production. This will prevent it from spreading to other parts of the network.
2. Deploy phase of a container
It is important that you focus on configuring your Kubernetes infrastructure securely before you deploy the workloads. You must understand what applications you are deploying and how, from where, so you can easily identify and respond to the possible threats.
You must have a basic understanding of components, clusters, namespaces, involved nodes, deployed pods, deployments, and run privileges. On top of that, your workload should have an understanding of what data it accesses or checks for. By dividing the workload into different namespaces, you can contain potential attacks to a single namespace in order to prevent them from spreading to others. You can also limit errors by using authorized access and controlling traffic between pods.
You must have the policy to ensure access privileges are secured for any container on the network. You should avoid deploying code from unknown sources by using an authorized image. Label your deployment with appropriate names to make scanning and resolution easier.
3. Runtime phase of a container
You can avoid some of the vulnerabilities by getting insight into the runtime environment for detecting any possible threat for running the containers. Such a process involves monitoring the processing activity, network communications, services, and the third party.
You can also compare the observed and the expected results of the system to identify the attack or vulnerability. Apart from this, you can extend the scanning process to the deployments to avoid further attacks. Kubernetes comes with various in-built controls for preventing attacks by monitoring the network traffic for unsecured communication.
Kubernetes Security Checklist
You should follow the below recommendations.
- Always use distro-less images and try to add only the necessary components.
- Try to use the minimal host OS, end read-only mounts for more control.
- Always scan the vulnerability of the images along with the OS images and sources of image.
- You should try a namespace for segmenting the cluster logically.
- Always ensure that the network segmentation is in place before deploying into production. Define the ingress and egress properly to ensure connections are routed properly.
- Avoid running applications as root. Alternatively, you can use a read-only root filesystem to prevent attacks depending on installed software.
- You can also automate the scanning process of images within the CI/CD pipeline. Try running CIS benchmark security tests.
- You can also leverage the built-in controls for running containers within Kubernetes like configuring the security context.
Built-in security features
Security at every phase of the Kubernetes is important thus it needs to be handled perfectly. Kubernetes security measures must be in place from the beginning all the way through to the end. Ensure that you always update Kubernetes and secure etcd. It should be standard practice to use TLS for all client connections. Below are some of the built-in security features to consider:
- Open policy agent (OPA) – it helps in unifying the policy enforcement using a high-declarative language that will help in specifying the policy as code. By using the policy decision-making capabilities of your software, you will save a lot of time. Using this feature you do not have to recompile or reconfigure your Kubernetes API to enforce your custom policies.
- Pod security policy (PSP) – you can define some conditions for running the pods.
- Role-based access control – it helps in managing the authorization access. Admins can dynamically configure the access policies for a particular user.
- Network policies – it helps in defining the rules for the pods to communicate.
You need a proper understanding of the complete Kubernetes infrastructure to know when and where you can use these pre-built tools and techniques. The same applies to identifying when and where vulnerabilities appear. In order to take advantage of Kubernetes benefits, you must ensure Kubernetes security.
If you are new to Kubernetes, then you may consult a third-party team for getting started with cluster orchestration depending on what type of application you want to run. Maintaining and managing complete security throughout the different phases of the Kubernetes lifecycle is important for better results and enhanced efficiency. As we discussed above, you can improve system throughput by implementing the best security practices within your system.