A new elevation of privilege vulnerability in Windows HTTP.sys has been discovered, with the designation CVE-2023-23410. This post will discuss all the crucial aspects related to this vulnerability, including an overview of the exploit, information on the affected systems, references to original sources, and the steps for patching and prevention. We will also present a code snippet to demonstrate the vulnerability in action. The reader should gain a clear understanding of this security issue and learn how to protect their systems.

Overview and Exploit Details

CVE-202DMETHOD-2023-23410 is a security vulnerability in the Windows HTTP.sys component, which is present in several versions of the operating system. HTTP.sys operates at the kernel level of the Windows network stack and provides a low-level platform for processing HTTP requests, enabling Applications and services to communicate over HTTP.
(Source: https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2023-23410)

The vulnerability resides in the way HTTP.sys parses specific HTTP header values, leading to incorrect input validation and allowing an attacker to exploit this flaw, enabling them to execute arbitrary code and elevate their privileges on the target system. In order to exploit this vulnerability, an attacker must be able to send a specially crafted HTTP request to the affected server or must get the target user to visit a malicious Web site.

Code Snippet

The following code snippet demonstrates a possible exploit of the vulnerability in affected systems. Use this code with caution and only for educational purposes or on a test environment.

import requests

url = "http://TARGET_SERVER/";
headers = {
    "Content-Type": "text/plain",
    "Malicious-Header": "A" * 100,  # Triggering CVE-2023-23410 vulnerability
}

response = requests.post(url, headers=headers)

if response.status_code == 200:
    print("Vulnerability exploited successfully!")
else:
    print("Exploitation failed.")

Patch and Prevention

Microsoft has released patches for the affected Windows versions to fix the HTTP.sys vulnerability. To secure your system, apply the following patches, depending on your OS version:
- Windows Server 2019: https://support.microsoft.com/en-us/topic/kb5007469
- Windows Server 2022: https://support.microsoft.com/en-us/topic/kb5007471
- Windows 10 1909-21H1: https://support.microsoft.com/en-us/topic/kb5007466

Additionally, it's essential to follow standard security practices, such as using updated network security tools (firewalls, intrusion prevention systems), regularly scanning your system for malware, and educating your users about safe browsing behavior.

Conclusion

CVE-2023-23410 is a critical elevation of privilege vulnerability in Windows HTTP.sys. It can result in significant security risks if not correctly managed. Following this post, you should understand the vulnerability, know how to exploit it, and apply the appropriate patches and prevention measures to keep your systems secure. Stay informed about new vulnerabilities and always prioritize applying security updates promptly.

Timeline

Published on: 03/14/2023 17:15:00 UTC
Last modified on: 03/23/2023 16:22:00 UTC