Vulnerable code sample

import urllib.request
import urllib.error

# This is a simplified representation of the utility function that makes the web request.
# In the actual pyLoad source, this uses pycurl, which also supports protocols
# like file://, gopher://, etc., leading to the vulnerability.
def get_url(url, post=None):
    """
    Fetches the content of a given URL.
    No validation is performed on the URL, its protocol, or the target IP address.
    """
    try:
        # urllib.request.urlopen, like pycurl, can handle various protocols
        # including file://, which is a key part of the vulnerability.
        with urllib.request.urlopen(url) as response:
            return response.read().decode('utf-8', errors='ignore')
    except urllib.error.URLError as e:
        # The original vulnerability allowed for error-based discovery.
        # Returning the error helps represent this aspect.
        return f"Error: {e}"


class Api:
    """
    A representative class mimicking the vulnerable part of the pyLoad API.
    """

    def __init__(self):
        """
        In the real application, self.core would be initialized with the
        main pyLoad core object.
        """
        # This is a placeholder for demonstration purposes.
        self.core = type('Core', (object,), {
            'package_manager': type('PackageManager', (object,), {
                'add_package': lambda name, data, pid: (name, data, pid)
            })()
        })()

    def parse_urls(self, urls, password=""):
        """
        Parse urls for packages. This is the vulnerable function.
        It takes a URL from an authenticated user and fetches its content
        without any validation.
        """
        # THE VULNERABILITY:
        # The user-provided `urls` variable is passed directly to a function
        # that makes a server-side request. There is no check to ensure the
        # URL is safe, does not point to an internal resource, or uses a
        # restricted protocol.
        data = get_url(urls, post={"pass": password})

        # The fetched data is then processed, completing the SSRF chain.
        return self.core.package_manager.add_package(
            "Crawled from %s" % urls, data, -1
        )