D-Link DIR-823X Command Injection Vulnerability in HTTP POST Request Handler

A critical command injection vulnerability has been identified in the D-Link DIR-823X router, specifically in firmware versions 240126 and 240802. The issue arises in the HTTP POST request handler for the 'diag_nslookup' form, where the 'target_addr' parameter can be manipulated to execute arbitrary operating system commands. This vulnerability can be exploited remotely, but requires authentication.

Impact

Successful exploitation allows for arbitrary command execution on the affected device.

Reproduction

To reproduce this vulnerability, send an authenticated POST request to the '/goform/diag_nslookup' endpoint. Include a payload in the 'target_addr' parameter that exploits the command injection vulnerability. This can be done using a tool like Burp Suite or by crafting a custom script that sends the appropriate HTTP request.