kCTF is a Kubernetes-based infrastructure for CTF competitions


kCTF is CTF infrastructure written on top of Kubernetes. It allows you to manage, deploy, and sandbox CTF challenges.

Try it – it takes 5 minutes to get started

We built kCTF to help CTF organizers have great CTF infrastructure tooling, and to give challenge authors an environment where they can build and test their challenges without having to learn about Kubernetes, while also allowing Kubernetes experts to use all the features they are accustomed to.

Versatile Specialized Secure
A simple challenge can be configured in a single Dockerfile. More complex deployments can use all Kubernetes features. Common CTF needs are provided as services (proof of work, healthchecks, DNS and SSL certificates, network fileshare). kCTF was built by Google’s Security Team with the goal of hosting untrusted, vulnerable applications as part of CTF competitions.


You can have a local challenge running in 5 minutes.

See the Local Testing Walkthrough to get started with a local challenge.

Google Cloudshell Codelab

To try this out on a real server, try out the Google Cloudshell codelab.

Open in Cloudshell

Online demo

We have a fake challenge running, you can see what an isolated challenge would look like by connecting directly to:

nc kctf.vrp.ctfcompetition.com 1337

If you are able to break out of it, you can earn up to $133,337 USD.

Tip: Execute bash -i 2>&1 to get an interactive bash session.

Available Documentation