Patched code sample

import ssrf_requests
import requests
from PIL import Image
from io import BytesIO

# The vulnerability existed because a user-supplied URL was fetched directly.
# The fix involves using a library that validates the URL and blocks requests
# to internal or private IP addresses, thus preventing SSRF.
#
# The code below represents a fixed version of such a function.

def get_image_info(image_url: str):
    """
    Safely fetches an image from a URL and returns its dimensions.

    This function uses the `ssrf_requests` library to prevent Server-Side
    Request Forgery (SSRF) attacks by ensuring the requested URL does not
    point to an internal or private network resource.
    """
    # Use a session that blocks SSRF attempts by default.
    session = ssrf_requests.Session()

    try:
        # The `session.get` call will raise an `ssrf_requests.exceptions.SSRFException`
        # if the URL targets a private/reserved IP address.
        with session.get(image_url, stream=True, timeout=5) as response:
            response.raise_for_status()
            
            # Process the image only if the request was safe and successful
            image = Image.open(BytesIO(response.content))
            return {
                "width": image.width,
                "height": image.height,
                "format": image.format,
            }
    except (requests.RequestException, ssrf_requests.exceptions.SSRFException) as e:
        # Handle exceptions from both network errors and detected SSRF attempts
        print(f"Could not retrieve or process image from {image_url}: {e}")
        return None