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All labs/skf-des-yaml

Web

OWASP SKF YAML Deserialization

A Flask page whose content comes from a base64-encoded YAML document in the URL, parsed with PyYAML's unsafe yaml.load.

Not startedDockercommit 2ce437dx86_64 · aarch64Secret

Objective

Craft a YAML document that makes PyYAML run a command on the server when it is loaded (insecure deserialization).

The brief for this lab lives in its repository.

Submit evidenceSecret

Launch the lab

Open it in the Cyber CTF launcher, or run it yourself with Docker Compose.

Open in the launcher Source code

›Run it manually

$git clone https://github.com/CyberCTF/skf-des-yaml && cd skf-des-yaml && docker compose up -d

Without the launcher, the lab uses its public development evidence: great for practice, but it won't complete the lab.

Details

Category: Web
Difficulty: Medium
Evidence: Secret
Runtime: Docker
Runs on: x86_64, aarch64
Commit: 2ce437d
Repository: CyberCTF/skf-des-yaml