What is Kubernetes Security?
Kubernetes is a portable, open-source platform for managing containerized workloads and services that facilitates both declarative configuration and automation. The extensible nature, speed and portability offered by Kubernetes, along with its ability to leverage a flexible microservices architecture, has made it an increasingly popular container solution and adoption has grown considerably over the last two years. However, Kubernetes, along with all container solutions, are challenging to secure because the multiple moving parts in its rapidly growing ecosystem create a broad attack surface, hence the need for a stringent, multi-level security strategy.
Making the Case for Kubernetes Security
While an increasing number of organizations are relying on Kubernetes to manage at least a portion of their container workloads, these efforts are often led by DevOps teams with security expertise and tools lagging behind adoption. The ephemeral qualities of Kubernetes are a double-edged sword; they offer increased agility in development but also complicate security because the attack surface is constantly changing.
When it comes to protecting Kubernetes systems, traditional security practices are not sufficient because they cannot keep up with enterprise-scale orchestration. The complex, dynamic nature of containers requires a unique set of security solutions that address everything from the applications they contain to the infrastructure they run on. Adding to the complexity is the fact that different security approaches are needed for every phase of an application: build, deploy and runtime.
Achieving & Maintaining Kubernetes Security
Achieving and maintaining Kubernetes security allows organizations to proactively mitigate threats, establish reliable reactive controls, and maintain compliance while leveraging the full power of this orchestration solution. This requires a concerted focus on four key elements: process, container images, connections, and runtime. Successfully integrating security across these phases will ensure networks and applications are protected from breaches, data leaks and malicious acts.
As it pertains to Kubernetes environments, security planning needs to start long before development does. Building security into the development process eliminates risks before deployment happens. This includes defining the type of information the application will handle so security policies can be established accordingly.
Containers are created out of layered files known as container images, and these images are the context within which the application runs. The security and quality of base images are critical because poorly configured images open containers to vulnerability and create an easy way for attackers to access a network.
In the Kubernetes environment, every pod can talk to every other pod, which offers distinct performance advantages. It also provides hackers with the opportunity to infiltrate a single container and then move laterally once inside the environment. For this reason, it is not enough to simply secure the components of the system; the connectivity between the components must be secured as well.
The container runtime is where containers are actually executed, and every Kubernetes infrastructure element presents its own attack surface. Because Kubernetes does not come with protections against a runtime attack, the goal in this phase is to achieve visibility into the running environment as well as to identify and respond to potential threats before they have an opportunity to escalate.
A Modern Approach to Kubernetes Security
Improving Kubernetes security is critical for any organization that leverages this popular orchestration solution. Accurics recommends practical approaches designed to help successfully integrate security across the aforementioned phases to ensure networks and applications are protected from breaches, data leaks and malicious acts. Minimizing the number of different tools required will also help improve consistency and visibility while reducing maintenance and redundancy. The Accurics platform has been designed to address these concerns.
On the process front, Kubernetes relies on codified infrastructure, and Policy as Code performs well in cloud native development processes to deliver consistency and velocity. This is also a great place to implement automated examination of third-party packages, images, and shells to ensure they are necessary and do not introduce risks. Accurics enables Policy as Code for Kubernetes, leveraging the same policy definition from editor to runtime.
Achieving Kubernetes security means securing the images used by the containers and securing how containers are pulled and used at runtime. Even base images from trusted sources are open to risk since making configuration changes introduces new variables. It is also necessary to detect malicious code that may exist inside a container image. This requires vulnerability scanning with an external tool since this scanning capability is not a feature of Kubernetes. And, developers should avoid creating extraneous images to minimize the attack surface of the overall application.
Securing connections means establishing policies that segment the network to prevent lateral movement of an attack, and defining roles and access controls to improve cluster security, ensuring only authorized users have full rights. Accurics’ Security as Code is effective here as it delivers proactive protection, detecting breach paths through pre-deployment assessments and enabling the runtime to detect and respond to violations.
When breaches or vulnerabilities are detected in a running container, patching the container is not a viable solution. Instead, the entire container must be replaced with a non-compromised version, which has the benefit of enabling strict version control. Security practices implemented in the previous three phases address Kubernetes security in the development process. Runtime controls such as the Accurics admission controller help secure the control plane, ensuring that non-compliant workloads and configurations cannot be accidentally or maliciously introduced into your clusters.
By focusing on these four areas, organizations can achieve next-level Kubernetes security and leverage the full power of the solution.