Challenge, Easy,  on  Kubernetes

Extracting and Decoding ServiceAccount Token from Kubernetes Secret

Omkar Shelke
by  Omkar Shelke

Scenario

You need to work in the mars namespace and identify the Secret that is linked to the ServiceAccount named mars-sa-v2.

After locating this Secret, extract the token value stored inside it and decode the Base64-encoded token.

Once decoded, save the resulting token content into the file /opt/token.

Finally, confirm that the /opt/token file is not empty and that its contents represent a valid JWT structure.

Perform the task on the dev-machine using the root user.

Test Cases

How to Author Challenges on iximiuz Labs

Instead of providing a subpar online editing experience, iximiuz Labs offers a helper CLI tool called labctl, allowing you to use your favorite text editor (or a full-featured IDE) to write content from the comfort of your local machine.

Install labctl CLI

curl -sf https://labs.iximiuz.com/cli/install.sh | sh

This will download and install the latest version of the labctl CLI. You only need to do this once per workstation.

Authorize labctl

labctl auth login

This will open a browser window asking you to authorize labctl to access your account. You need to do it after a fresh install of labctl and repeat it whenever the auth session expires.

Pull challenge content

labctl content pull challenge extracting-and-decoding-serviceaccount-token-from-kubernetes-secret-8cbb032a

This will create a local copy of the challenge content in a directory named extracting-and-decoding-serviceaccount-token-from-kubernetes-secret-8cbb032a. You only need to do this once per challenge.

Stream your changes

labctl content push -fw challenge extracting-and-decoding-serviceaccount-token-from-kubernetes-secret-8cbb032a

Run this command in a separate terminal to continuously upload your changes to the server while editing the challenge in your favorite text editor or IDE.

You can also use labctl to create, list, and delete your content. Learn more about the available commands: labctl content --help

Start challenge