Introduction

CdsCTF is a modern open-source Capture The Flag (CTF) platform based on Rust, offering highly customizable features such as problem set design and game hosting. Originally developed by ElaBosak233 (Ela) and continuously maintained.

This project is open source under the GPL-3.0 license. Any use or modification must comply with this open source license.

Features

Challenges

• Highly customizable challenges: Supports multiple challenge types and configuration options
• Diverse challenge types:：
  • Attachments: Challenges can carry fixed attachments for download
  • Dynamic environment: Automatically generated and dynamic flags are issued through container environment variables
• More powerful submission check strategies: A more flexible flag checking mechanism based on Rune scripts

Games

• Dynamic score: A dynamic score calculated based on difficulty coefficient, score upper and lower limits, and the number of ACs (Accepted).
• Ranking rewards: Extra proportions of scores are awarded to teams in the top ranks.
• Flexible challenge management: Challenges can be added or removed at any time during the competition, and freeze time can be set.

Virtualization

• Dynamic environment management based on Kubernetes: automatic creation, distribution and management of containers
• Resource limits: strict control over CPU, memory and storage resources for each container
• Network isolation control: selective allowance or prohibition of container access to the Internet
• Lifecycle: automatic cleanup of expired environments and support for environment renewal

Acknowledgements

Contributors

Thanks to everyone who has contributed to the project! Without you, CdsCTF would not be what it is today.

Stars