Insecure Deserialization

A Python Flask app uses pickle for session handling. Craft a malicious payload.

Vulnerable Code

import pickle
import base64

data = base64.b64decode(cookie)
session = pickle.loads(data)  # Vulnerable!

Create a pickle payload that when deserialized achieves arbitrary command execution and prints the flag.

The test will deserialize your payload and check that it executes echo 'FLAG{...}' successfully. Your print() statement shows the encoded payload for inspection.