Advanced Network Pivoting and Lateral Movement Analysis¶

Methodology for Authorized Penetration Testing¶

Modern internal environments are increasingly segmented. A professional penetration tester must understand how to navigate these segments once initial access is gained (assuming authorization). This article focuses on the "Pivoting" stage of a pentest, using legitimate tools to demonstrate network reachability.

Real-World Scenario¶

A consultant has gained access to a development workstation in the 10.10.10.0/24 subnet. The goal is to verify if the production database in 10.10.20.0/24 is reachable, which would indicate a violation of the NIST SP 800-125B virtualization security guidelines.

Implementation: Python-Based Port Scanner for Lateral Discovery¶

Instead of using noisy scanners that might be flagged, a customized Python script can perform targeted discovery.

import socket
import threading
from queue import Queue

# Prerequisites: Python 3.x, Target subnet authorization
target_subnet = "10.10.20."
port_list = [80, 443, 445, 3306, 3389]
print_lock = threading.Lock()

def scan_port(ip, port):
    try:
        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        sock.settimeout(0.5)
        result = sock.connect_ex((ip, port))
        if result == 0:
            with print_lock:
                print(f"[+] Found Open Port: {ip}:{port}")
        sock.close()
    except Exception:
        pass

def threader():
    while True:
        ip, port = q.get()
        scan_port(ip, port)
        q.task_done()

q = Queue()
for _ in range(20): # Thread count
    t = threading.Thread(target=threader)
    t.daemon = True
    t.start()

# Scanning specific range in authorized subnet
for host in range(1, 255):
    for port in port_list:
        q.put((f"{target_subnet}{host}", port))

q.join()

Step-by-Step Execution¶

1. Verify Scope: Ensure the 10.10.20.0/24 range is explicitly listed in the Rules of Engagement (RoE).

2. Establish Pivot: Use an SSH tunnel or a SOCKS proxy (e.g., ssh -D 1080 user@pivot-host).

3. Execute Discovery: Run the Python script to identify misconfigured access control lists (ACLs).