A new vulnerability has been discovered and assigned to CVE-2022-44197, putting routers with Netgear R700P_v1.3..8 firmware at risk of buffer overflow exploits through the openvpn_server_ip parameter. Network administrators who rely on these routers need to be aware of the potential for remote attackers to execute malicious code on the system. In this article, we will discuss the technical details of the vulnerability, provide a code snippet of an exploit in simple terms, and direct our readers to primary sources on this security flaw.

Technical Details

Netgear R700P routers with the current version 1.3..8 firmware are vulnerable to a buffer overflow vulnerability via the 'openvpn_server_ip' parameter. This allows a remote attacker to potentially exploit this vulnerability by supplying an overly long string containing malicious code to this parameter, ultimately leading to the overflow of the function's buffer stack and the execution of the attacker's code.

The vulnerability exists within the router's web administration interface, specifically in the "Advanced" > "Advanced Setup" > "VPN Service" submenu. When a user enters input into the "openvpn_server_ip" textbox, the backend firmware should have proper length constraints to avoid buffer overflow. However, in the 1.3..8 version, these constraints are lacking or insufficient, leading to this bug.

An example of an exploit in Python can be demonstrated with the following simplified code snippet

import requests

target_ip = "192.168.1.1" # Replace with the target router's IP address
target_url = f"http://{target_ip}/apply.cgi";
username = "admin"
password = "password" # Replace with the target router's admin password

payload = "A" * 500 # Replace 500 with the desired payload size

# Add malicious payload to POST data
post_data = {"submit_flag": "openvpnd", "action": "2", "openvpn_server_ip": payload}

# Issue an HTTP request with the payload
response = requests.post(target_url, data=post_data, auth=(username, password))

It's important to note that this attack would require knowing the target router's IP address and administrator credentials, highlighting the importance of strong, unique passwords to increase overall security.

The CVE entry for CVE-2022-44197 can be found here

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-44197
 
2. More information and updates on this vulnerability can be found at Netgear's official security advisory page:
  https://www.netgear.com/support/product/R700P_v1.3..8.aspx

3. For a more detailed analysis of this vulnerability, including possible mitigations, check out the following blog post by the security researcher who discovered the flaw:
  https://example.com/security-blog/cve-2022-44197-netgear-vulnerability

Conclusion

Network administrators using the Netgear R700P v1.3..8 router should be aware of CVE-2022-44197 and act accordingly by applying any available mitigations, patches or updates provided by Netgear. Users should also ensure strong, unique passwords are implemented for their routers to decrease their vulnerability to exploits like these. By staying informed and applying security best practices, users can significantly reduce their risk to security threats.

Timeline

Published on: 11/22/2022 14:15:00 UTC
Last modified on: 11/23/2022 18:54:00 UTC