Kubernetes Security Risks: 10 Vulnerabilities You Need to Know

We'll cover the 4 C's of Kubernetes security and the biggest disadvantages of Kubernetes along with a solution that will help you find Kubernetes security risks and quickly remediate them.

Kubernetes provides a far more efficient platform for running, deploying, and managing distributed systems. This has made it the No. 1 choice and go-to solution for organizations looking for a suitable means of streamlining the development process.

But despite its robust architecture and properties, Kubernetes has its own fair share of security challenges. This post will introduce some of the security concerns you should consider due to the complex environment and deployment process of Kubernetes. We’ll also check out the importance of Kubernetes security and understanding security best practices.

Then, we’ll cover the 4 C’s of Kubernetes security and the biggest disadvantages of Kubernetes. This post will present a solution that will help you find Kubernetes security risks and issues, and quickly remediate them.

Importance of Kubernetes Security

To stay ahead of potential risks of attacks, it’s important to implement security measures that will safeguard IT infrastructure. Kubernetes makes it easier to deploy, scale, and manage applications. Most of these systems are related to finances—for example, trading applications or e-commerce apps. To make sure that these applications run smoothly, advanced security needs to be prioritized.

A compromise on Kubernetes clusters could result in severe damage and significantly impact the systems. For example, the reputation of the organization could be at stake if there is a compromise. This is because people may no longer trust the services offered by the organization. This might result in the loss of both existing and potential new customers.

Kubernetes security is important to protect applications from attackers because an attack could lead to a possible loss of funds. An attack also can result in exposing stored data, like customers’ credit card details or personal health data. This compromise can lead to further damage, like theft of a customer’s funds and lawsuits.

Kubernetes security provides better insights into an application’s posture. It reveals potential risks and discovers vulnerabilities in Kubernetes and its containers. By implementing Kubernetes security, organizations can reduce the risks of application failure.

A proactive approach to securing Kubernetes containers can reveal misconfiguration and a lack of consistency, among other vulnerabilities. Sometimes, developers might make the mistake of granting higher privileges to sensitive data or administrative operations to users or an account. This can cause severe damage and lead to potential cyberattacks if not identified quickly.

Kubernetes security can help prevent attackers from exploiting vulnerable parts of an application.

Top 10 Kubernetes Security Risks

As organizations continue to adopt Kubernetes, security risks continue to increase, and so does the need to implement security measures that will ensure the protection of applications from vulnerabilities. Because Kubernetes is not secure by default, an insecure setup and misconfigured Kubernetes container can lead to vulnerabilities that could make a system open for attacks.

In this section, we’ll discuss the top Kubernetes security risks, in no particular order.

1. Poor secrets management

Sensitive data, such as passwords or tokens, are stored using something called “secrets” in Kubernetes. This is, in fact, an efficient method of protecting unregulated access to sensitive data by unauthorized individuals or entities. However, if these secrets are not properly managed, it can lead to the system being vulnerable and open for unauthorized access.

Poor management of secrets can cause an attacker to gain access to API keys and other sensitive data that permits them to carry out certain functions.

Possible solutions

1. Always encrypt sensitive data before storing it with secrets.
2. By default, Kubernetes does not offer secret encryption, but you can configure it.
3. You also have to configure access control to limit access to secret data. This will limit unauthorized access and control vulnerability.

2. Poor implementation of role-based access control

Role-based access control (RBAC) is a security practice that is implemented to grant users permission in an application based on their positions. For example, an admin will have more permission than a regular user of the application because they are ranked higher in an organization.

If properly implemented, RBAC will guarantee that only qualified users will gain access to certain features in an application. Just like in the scenario of an admin user and a regular user, an admin user might have permission to change crucial settings that a regular user may not be able to change.

If the implementation of RBAC is not correct, it can lead to a breach. This can cause unauthorized users to have access to administrative roles.

Possible solutions

1. Avoid using RBAC policies that are too permissive.
2. Design RBAC policies for particular resources, and assign them to authorized and relevant users.
3. Reduce exposure of RBAC policies; this will ensure that only people with relevant roles can access data in the software development life cycle.

3. Misconfiguration of deployments workloads

This type of vulnerability risk happens when there is a misconfiguration in the workload settings. With this type of vulnerability, attackers gain access to cluster networks and cause severe damage.

Possible solutions

1. Adopt infrastructure as code tools such as SentinelOne to define and manage your deployments declaratively.
2. Avoid hard-coded credentials in configuration files.
3. Integrate your deployment pipeline with CI/CD tools. This will automate the detection of misconfiguration, thus reducing configuration errors.

4. Inadequate cluster monitoring and auditing

Cluster monitoring and log audits provide insights that can detect potential threats and attack incidents. This allows organizations to identify and correct an application’s vulnerabilities before they become full-blown attacks.

If monitoring is poor and inadequate, it becomes difficult to detect potential threat incidents. The result of this is that detecting threat incidents late will result in making late decisions. Instead of being proactive toward threats, organizations might have to wait for an attack to occur before it’s detected.

Possible solutions

1. It’s important to check for anomalies and possible threat behaviors. This will indicate vulnerabilities on time before they are exploited.
2. To keep the cluster safe, you should watch and monitor the cluster status.
3. You should gather security data and analyze the security status and posture of your application.

5. Misconfigured network access control

In Kubernetes, pods are allowed to connect external addresses outside their clusters. This allows pods to communicate and share resources. But to protect the level of connection between pods, a network access control policy is implemented. These policies will limit how a pod in a cluster communicates with other pods.

The wrong configuration of network access control will mean that the cluster can be accessed and connected from all sources. This can give attackers the privilege to access resources from one pod to another in a connected cluster.

Possible solutions

1. Implement network policies that will limit and control access to cluster resources.
2. Assign network permissions based on roles rather than individuals. Each role should have clearly defined access rights.
3. Require users to provide additional authentication factors before accessing network resources.

6. Unlimited resource requests

It’s important to always limit the number of requests that can be made on a single Kubernetes request. This is because if there’s no limit on how resource requests are made, the security of containers and other resources can be at stake. For instance, when the number of requests is more than the available resources, then there will be a shortage of resources in the node.

Possible solutions

1. Calculate and assign resource requests correctly to avoid misuse and abuse.
2. Implement auto-scaling to dynamically allocate more resources when needed and reduce them when demand decreases.
3. Implement efficient memory management techniques to recover unused resources.

7. Vulnerable images

The use of unsecured container images presents a significant level of risk that can lead to a slowdown or delays in deploying and running applications. When container images are unsecured, they may contain vulnerabilities like malware, outdated software, or misconfiguration. This can lead to security breaches and performance issues.

Possible solutions

1. Use vulnerability scanning tools like SentinelOne to automatically detect security vulnerabilities in container images before they are deployed.
2. Use image-signing tools to verify the authenticity of container images before deploying them.
3. Avoid using outdated or unsupported versions of container images.

8. Insecure kubernetes API

Using Kubernetes APIs requires significant security approaches. This is important to follow because attackers can exploit unprotected API endpoints to gain access to an organization’s system. This can lead to several attacks, such as distributed denial of service or injection attacks. These attacks can affect the system severely and cause a loss of data and sometimes a slowdown in deployment.

Possible solutions

1. Implement a very strong API authentication approach that will check APIs before they are allowed to access data.
2. Encrypt API communication by enforcing transport layer security. This ensures that all communications between clients and the API server are encrypted.
3. Configure API rate limiting to prevent abuse or DoS (denial of service) attacks.

9. Runtime permissive errors

Having a container image with vulnerable permissive policies can lead to access of the entire cluster by the attacker during runtime. It is important to implement a protection principle that prevents or limits the number of privileges assigned during runtime. This is because Kubernetes containers run on the work nodes, and they are controlled by the operating system. If there are no principles to check the type of privileges, then this can lead to vulnerability during runtime.

Possible solutions

1. Use strict permission policies to enforce rules to control runtime workloads.
2. Ensure that files and directories have the appropriate read, write, and execute permissions for the user or group running the application.
3. Review your code for runtime permission checks. Ensure that the application handles permission-related errors instead of crashing.

10. Improper data storage and access limitations

With the Kubernetes StatefulSet resource, you can deploy different types of applications and tools, such as data analytics and machine learning tools, to Kubernetes that are simple and scalable. However it’s important to note that implementing policies will limit access to pods data. This is because storage in Kubernetes is provided by external systems, and you need to make sure that data is not accessible to everyone.

Possible solutions

1. Make sure data is encrypted before storage. This is a good practice that keeps data secure.
2. Always make use of the least privilege principle to control access to data.
3. Classify sensitive data for more security measures.

5 Kubernetes Security Best Practices

• Implement proper network policies to control cluster access. With the right network control policies in check and place, teams and organizations can identify anomalies. This policy can help prevent granting access to cluster resources to attackers. The implementation of this policy happens on a three-level identification basis: namespaces, IP blocks, and allowable pod identifiers. By properly implementing this policy, you can monitor your pod and only grant access to entities with proper permissions.
• Use zero-trust architecture. A zero-trust architecture is a security approach that always verifies a request coming into a cluster network. Since Kubernetes clusters and nodes can communicate, attackers might capitalize on this ability to spread their attacks across clusters. It is important to employ a security feature that checks the validity of network requests, even if they come from connected nodes.
• Implement a strong monitoring and auditing policy. Comprehensive monitoring will perform an all-around check on Kubernetes clusters and identify existing and potential vulnerabilities. This practice will help you identify vulnerable clusters and act fast to prevent further exploitation.
• Make use of container images. Container images are immutable files that contain all the components needed to create a container. Since container images are immutable, they are helpful and very handy in the transmission of original containers. This is because container images prevent modifications during runtime.
• Use secure methods to manage secrets. Secrets contain highly sensitive data that can grant access to clusters and nodes. Some of this data is API and access keys. If an attacker exploits stored secrets, they can control higher permissions and perform great damage. It is important to implement encryptions of Kubernetes secrets. This practice will ensure that it won’t be visible or humanly readable.

Final Words

Kubernetes is a widely acceptable platform for creating and running containerized platforms. It is easy to set up and use, and because of this, organizations prefer to use it for the orchestration of their container applications.

With simplicity comes the need to implement best practices to secure applications. Since Kubernetes is built for easy setup, it has its own fair share of security challenges. This post walked through the importance of Kubernetes security, the risks associated with using Kubernetes, and some security best practices.

FAQs

What are the 4 C’s of Kubernetes security?

The four C’s are cloud, code, cluster, and container.

• Cloud

Whether a cluster is built using a personal data center or cloud provider, it is important to implement security best practices that will secure the underlying infrastructures.

• Code

An insecure code presents opportunities for attackers to exploit Kubernetes environments. An attacker can gain access to cluster secrets if proper management is not a priority. Exposing secrets in the code base without proper encryption makes it visible to anyone and everyone, and this is a bad practice that can lead to vulnerabilities.

• Cluster

Implementing proper configurations of Kubernetes APIs is one of the security measures of Kubernetes clusters. It is important to have the right configuration settings to keep and create a secure environment for applications that are part of the cluster.

• Container

Container security involves configuring components of a Kubernetes container in a way that avoids granting excess permissive roles to users. If a container grants too many permissions and privileges to a particular user, then there is a high tendency that when that user comes under attack, the whole system becomes open to an attack. So, it is important to always scan the Kubernetes container for these types of misconfigurations and other potential vulnerabilities.

What are the biggest disadvantages of Kubernetes?

Although organizations make use of Kubernetes as their No. 1 choice for container orchestration for deploying and scaling containerized applications, it still has its fair share of disadvantages. One of the biggest disadvantages of Kubernetes is its default configuration. By default, Kubernetes is not configured to be secure. This is why it is important to take security considerations seriously while configuring your Kubernetes container.

This requires continuous protection of cluster resources, which could be time-consuming and complex. Kubernetes security requires a series of checks and monitoring to detect future potential risks. Kubernetes offers some security features that could be used to secure applications, but they are not configured to be used by default.

The simple usage of Kubernetes has introduced several challenges such as security risks in container images, runtime vulnerabilities, and cluster misconfigurations.