CVE-2025-10401 Overview
CVE-2025-10401 is a command injection vulnerability affecting D-Link DIR-823x routers running firmware versions up to 250416. The flaw resides in the /goform/diag_ping endpoint, where the target_addr parameter is passed to a system command without proper sanitization. Authenticated attackers can manipulate this parameter to inject arbitrary operating system commands that execute in the router's context. The vulnerability is classified under CWE-74 (Improper Neutralization of Special Elements in Output). A public proof-of-concept has been released, increasing the likelihood of opportunistic exploitation against exposed devices.
Critical Impact
Authenticated remote attackers can execute arbitrary commands on affected D-Link DIR-823x routers through the diagnostic ping function, potentially gaining full control of network infrastructure.
Affected Products
- D-Link DIR-823x router (hardware)
- D-Link DIR-823x firmware versions up to 250416
- D-Link DIR-823x AX3000 model (per public PoC)
Discovery Timeline
- 2025-09-14 - CVE-2025-10401 published to NVD
- 2026-04-29 - Last updated in NVD database
Technical Details for CVE-2025-10401
Vulnerability Analysis
The vulnerability exists in the diagnostic ping functionality exposed through the router's web management interface at the /goform/diag_ping endpoint. The target_addr HTTP request parameter is intended to accept an IP address or hostname for the router to ping. Instead of validating the input as a valid network address, the firmware passes the value directly to a shell command execution function. Attackers append shell metacharacters such as semicolons, backticks, or pipe operators to inject arbitrary commands. Successful exploitation grants command execution with the privileges of the web server process, which on consumer D-Link routers typically runs as root.
Root Cause
The root cause is improper neutralization of special elements passed downstream to an operating system command. The diagnostic handler concatenates user-supplied data into a system call without applying allowlist validation or argument escaping. This matches the CWE-74 injection pattern common across embedded router firmware that wraps Busybox utilities for diagnostic features.
Attack Vector
Exploitation requires network access to the router's web management interface and low-privilege authenticated credentials. An attacker submits a crafted POST request to /goform/diag_ping with the target_addr field containing a shell command injection payload. Because the vulnerability resides in the diagnostic ping handler, the injected commands run alongside the legitimate ping invocation. Refer to the public proof-of-concept on GitHub for technical details on the request structure and payload format.
No verified exploit code is reproduced here. The injection mechanism follows the standard pattern of appending shell metacharacters to the vulnerable parameter value.
Detection Methods for CVE-2025-10401
Indicators of Compromise
- HTTP POST requests to /goform/diag_ping containing shell metacharacters such as ;, |, &, $(), or backticks in the target_addr parameter.
- Unexpected outbound network connections from the router to attacker-controlled infrastructure following diagnostic page access.
- Unauthorized modifications to router configuration files or the presence of new processes spawned from the web server parent.
Detection Strategies
- Inspect web server access logs on the router for requests to /goform/diag_ping that include non-IP characters in the target_addr field.
- Monitor network traffic for HTTP requests to D-Link administration interfaces from non-administrative source addresses.
- Deploy network intrusion detection signatures that flag command injection patterns targeting D-Link goform endpoints.
Monitoring Recommendations
- Capture and review router system logs for shell command execution events that do not correlate with administrator activity.
- Track DNS queries originating from router IP addresses to identify command-and-control beaconing or payload downloads.
- Alert on configuration changes to the router that occur outside scheduled maintenance windows.
How to Mitigate CVE-2025-10401
Immediate Actions Required
- Restrict access to the router's web management interface to trusted internal management networks only.
- Disable remote (WAN-side) administration on all D-Link DIR-823x devices until a patch is applied.
- Rotate all administrative credentials for the router and any accounts that may share those credentials.
- Audit the device for signs of compromise, including unauthorized configuration changes, new firewall rules, or modified DNS settings.
Patch Information
At the time of publication, no vendor advisory or firmware patch from D-Link has been associated with this CVE. Monitor the D-Link official website and the VulDB entry for this issue for updated patch availability.
Workarounds
- Place the affected router behind an upstream firewall and block inbound access to TCP ports used by the web management interface.
- Apply network segmentation to isolate the router's management plane from user and guest network segments.
- Replace end-of-support or unpatched DIR-823x units with a currently supported router model if no firmware update is published.
# Example: block external access to the router web interface using upstream firewall rules
iptables -A FORWARD -p tcp -d <ROUTER_IP> --dport 80 -j DROP
iptables -A FORWARD -p tcp -d <ROUTER_IP> --dport 443 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
