Today, we're going to explore the CVE-2022-44188 - a critical buffer overflow vulnerability affecting Netgear R700P routers running firmware version V1.3..8. Specifically, this vulnerability targets the enable_band_steering parameter of the /usr/sbin/httpd binary, potentially allowing remote attackers to execute arbitrary code, launch denial of service attacks, or gain unauthorized access to your home or office's internal network.

We'll break down the details behind this exploit, offer a look at some code snippets, and provide links to original references and resources to help mitigate the issue.

Vulnerability Details

CVE-2022-44188 affects the /usr/sbin/httpd binary in Netgear R700P routers running firmware version V1.3..8. This vulnerability is a result of improper input validation on the enable_band_steering parameter, which could allow an attacker to provide specially crafted input that triggers a buffer overflow in the router's memory.

The buffer overflow occurs due to a design flaw in how the router processes HTTP requests. When parsing specific HTTP requests, such as those containing the enable_band_steering parameter, the router may not properly handle request data of a certain length, resulting in a memory corruption issue. This can ultimately cause the router to crash or, in some cases, lead to remote code execution.

Here is a code snippet outlining the vulnerable function in the Netgear R700P V1.3..8 firmware

void process_request() {
    char request_param[64];
    ...
    get_param_value("enable_band_steering", request_param, sizeof(request_param));
    ...
}

In this snippet, we can see that the get_param_value() reads the value of the enable_band_steering parameter into the request_param buffer. However, there is no proper input validation in place to ensure that the supplied input data doesn't exceed the buffer size (64 bytes) and overwrite adjacent memory.

Exploitation

To exploit this vulnerability, an attacker can send a crafted HTTP request to the /usr/sbin/httpd binary that includes the enable_band_steering parameter with a malicious payload. The payload is designed to overwrite adjacent memory areas and corrupt the router's memory to the attacker's advantage.

In some cases, this buffer overflow attack can also lead to remote code execution, where the attacker can run arbitrary code on the router's system. This, in turn, gives the attacker unauthorized access to your internal network and potentially sensitive information.

Mitigation

As of the time of writing this article, Netgear has not yet released a firmware update addressing the CVE-2022-44188 vulnerability. Therefore, it is essential to keep an eye out for future firmware updates and apply them as soon as they become available.

In the meantime, consider following these best practices to mitigate the risks associated with this vulnerability:

1. Disable remote management - Most routers allow remote administration from the internet. Disable this feature if it's not needed to reduce exposure to potential attacks.

2. Use strong and unique passwords - Change the router's default username and passwords to strong, unique credentials to prevent unauthorized access.

3. Implement network segmentation - Segment your internal network and restrict access to only the necessary devices and subnets to minimize the potential damage if a device is compromised.

4. Regularly review logs - Monitor your router's logs for any suspicious activities or unauthorized access attempts.

For more information about CVE-2022-44188, check out the following resources and references

1. CVE-2022-44188 - NVD Detail
2. Netgear Security Advisory
3. OWASP IoT Project: Router Security

Conclusion

The CVE-2022-44188 vulnerability in Netgear R700P V1.3..8 firmware serves as a sober reminder of the ongoing security threats associated with internet-connected devices. As users and administrators, we must be proactive and vigilant in addressing these vulnerabilities to protect our networks, devices, and privacy. Stay informed, follow best practices, and implement recommended updates to stay one step ahead of the attackers.

Timeline

Published on: 11/22/2022 14:15:00 UTC
Last modified on: 11/23/2022 19:22:00 UTC