Kubernetes Deployments Best Security Practices with Manifest Files

Pre-requisites: Kubernetes 

The container orchestration technology Kubernetes makes it possible to deploy and manage applications in a containerized environment. To protect the security and integrity of your apps and data, it is crucial to follow security best practices, as with any technology. These are several security best practices for Kubernetes deployments:

1. Use the most recent version of Kubernetes: To benefit from the most recent security features and updates, always utilize the most recent version of Kubernetes.

2. Put Role-Based Access Control (RBAC) into practice: RBAC enables you to manage and restrict access to your Kubernetes resources. Only allow those who truly need access.

3. Keep an eye on Kubernetes logs: Be alert for any irregularities or occurrences involving security. This can help you recognize security incidents more quickly and take appropriate action.

4. Do security assessments on a regular basis: Regularly do security assessments to check for vulnerabilities and ensure the security of your Kubernetes infrastructure.

5. Use network policies to manage traffic to and from your Kubernetes resources: Ensure that only relevant ports and protocols are accessible.

6. Make use of pod security policies: A pod’s security context is managed by pod security policies (PSPs). To make sure that Pods is operating in a secure environment, using PSPs.

7. Make use of a secure container image: Consistently make use of a secure container image from a reliable source. Before deployment, make sure the container image has been inspected for vulnerabilities.

8. Activate image signature verification: This makes sure the container image hasn’t been tampered with.

9. Make use of secrets management: Save confidential data, such as API keys and passwords, using Kubernetes secrets. Make sure that both at-rest and in-transit secrets are encrypted.

10. Utilize HTTPS for API communication: To ensure a secure connection between Kubernetes components, always use HTTPS for API communication.

You can make sure that your applications and data are secure in a containerized environment by adhering to these Kubernetes Deployments security best practices.

Namespace

Kubernetes namespaces are virtual clusters that can be used to separate resources and restrict access to those resources. They come with a manifest file. Pods, services, and deployments are examples of the resources that are described in YAML or JSON files called manifest files by Kubernetes.
When creating resources with a manifest file, you can specify the namespace in which the resources should be created. The “namespace” field in the metadata section of the manifest file can be used for this. For instance:

apiVersion: v1
kind: Pod
metadata:
 name: my-pod
 namespace: my-namespace
spec:
 containers:
 - name: my-container
   image: nginx
//This manifest file creates a pod named 
"my-pod" in the namespace "my-namespace" 
with an Nginx container.

RABAC 

A Kubernetes authorization technique called role-based access control (RBAC) uses roles and role bindings to regulate access to resources. RBAC bindings and responsibilities can be specified in a manifest file. Using the following manifest file as an illustration, a role called “my-role” is created and given read access to pods in the “default” namespace.

kind: Role
apiVersion: rbac.authorization.k8s.io/v1
metadata:
 name: my-role
rules:
- apiGroups: [""]
 resources: ["pods"]
 verbs: ["get", "list"]
 

To bind this role to a user or group, you can create a role-binding manifest file. For example, the following manifest file creates a role binding named “my-role-binding” that binds the “my-role” role to the “my-user” user:

kind: RoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
 name: my-role-binding
subjects:
- kind: User
 name: my-user
 apiGroup: rbac.authorization.k8s.io
roleRef:
 kind: Role
 name: my-role
 apiGroup: rbac.authorization.k8s.io
 

Activate image signature verification 

Container images’ authenticity and integrity can be confirmed using Kubernetes’ image signature verification feature. You must enable the ImagePolicyWebhook admission controller and set it up to utilize a validating webhook that conducts image signature verification in order to enable image signature verification.

The steps to activate image signature verification are as follows:

Step 1: Add the following flag to the kube-Episerver configuration to enable the ImagePolicyWebhook admission controller:

--enable-admission-plugins=...,
ImagePolicyWebhook,...

Step 2: Construct an image signature verification webhook that works with Kubernetes. This webhook should be set up to check the image signature using a public key.
Step 3: Establish an image policy that outlines which photos, depending on their signature, should be permitted. For instance, the following image policy only permits pictures that are signed with a particular public key:

apiVersion: policy/v1beta1
kind: PodSecurityPolicy
metadata:
 name: my-policy
spec:
 privileged: false
 # ...
 imagePolicy:
   requiredSignatures:
     - 0123456789abcdef0123456789abcdef01234567
 

Step 4: Create a pod security policy object in step 4 to apply the image policy to the cluster.