Vulnerable code sample

import os
from functools import wraps
from flask import Flask, request, jsonify

# --- Mock User and Permission System ---

# In a real app, this would come from a session or token
def get_current_user():
    # This user is explicitly denied tool management capabilities
    return {"id": "user-2", "permissions": ["workspace.chat", "workspace.rag"]}

# A decorator to check for permissions
def require_permission(permission_name):
    def decorator(f):
        @wraps(f)
        def decorated_function(*args, **kwargs):
            user = get_current_user()
            if permission_name not in user.get("permissions", []):
                return jsonify({"error": "Forbidden: You don't have the required permission."}), 403
            return f(*args, **kwargs)
        return decorated_function
    return decorator

# --- Mock Database ---
TOOLS_DB = {
    "1a2b3c": {
        "id": "1a2b3c",
        "name": "System Info Tool",
        "content": "import os\nprint(os.uname())"
    }
}

# --- Flask App ---
app = Flask(__name__)

# This endpoint is correctly protected.
# It serves as a contrast to the vulnerable one.
@app.route('/api/v1/tools/create', methods=['POST'])
@require_permission('workspace.tools')
def create_tool():
    # This code is never reached by the untrusted user
    data = request.get_json()
    tool_id = "new-id-xyz"
    TOOLS_DB[tool_id] = {"id": tool_id, "name": data["name"], "content": data["content"]}
    return jsonify(TOOLS_DB[tool_id]), 201

# VULNERABLE ENDPOINT: Missing the permission check
@app.route('/api/v1/tools/id/<string:id>/update', methods=['POST'])
def update_tool(id):
    if id not in TOOLS_DB:
        return jsonify({"error": "Tool not found"}), 404

    data = request.get_json()
    updated_tool_data = data.get("tool")

    if not updated_tool_data or "content" not in updated_tool_data:
        return jsonify({"error": "Invalid payload"}), 400

    # The vulnerability: An untrusted user can update the tool's code
    TOOLS_DB[id]["content"] = updated_tool_data["content"]
    
    # Simulate the dangerous execution of the updated code
    print(f"Executing updated code for tool {id}:")
    try:
        exec(TOOLS_DB[id]["content"])
    except Exception as e:
        print(f"Execution failed: {e}")

    return jsonify(TOOLS_DB[id]), 200

# Example usage to demonstrate the vulnerability:
# An attacker with the "untrusted_user" profile (without 'workspace.tools' permission)
# can successfully send a POST request to /api/v1/tools/id/1a2b3c/update
# with the following JSON body to execute arbitrary code:
#
# {
#   "tool": {
#     "content": "import os; os.system('echo Vulnerability exploited > exploited.txt')"
#   }
# }
#
# This request would be blocked on the /api/v1/tools/create endpoint,
# but it succeeds on the update endpoint due to the missing check.