Description

Netis NX10 firmware V4.0.1.5808 and V3.0.0.4142 contain an OS command injection vulnerability in the ping diagnostic handler that allows authenticated administrators to execute arbitrary shell commands as root by injecting into the IpAddr parameter. The parameter is interpolated directly into a shell command executed through system() with an incomplete denylist that only blocks spaces, pipes, semicolons, and ampersands, leaving command substitution and alternate field separator expansion available for exploitation.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.2",
  "pubDate": "2026-09-08T15:18:44.330Z",
  "pubdate": "2026-09-08T15:18:44.330Z",
  "executiveSummary": "The Netis NX10 router, specifically firmware versions V4.0.1.5808 and V3.0.0.4142, is susceptible to an OS command injection vulnerability within its diagnostic ping functionality.\nThe vulnerability originates from inadequate input validation within the IpAddr parameter processing logic, which allows an authenticated administrator to bypass existing security filters and execute arbitrary shell commands with root-level privileges.\nThe flaw stems from an incomplete denylist strategy that fails to account for command substitution and alternate field separators, rendering the system vulnerable to remote code execution.\nSuccessful exploitation requires authenticated administrator access to the device management interface. Once authenticated, an attacker can manipulate the ping request to escape the intended command context.\nThe impact of this vulnerability is critical, as it grants full control over the underlying operating system. Attackers can leverage this access to persist within the environment, intercept network traffic, modify device configurations, or utilize the compromised device as a pivot point for further attacks on the internal network.\nRemediation requires updates to the firmware input validation logic to enforce strict whitelist-based sanitization rather than denylist-based filtering.",
  "technicalDetails": "The vulnerability resides in the ping diagnostic handler component of the Netis NX10 web management interface. When a user initiates a diagnostic ping, the application captures the IpAddr parameter and passes it to the system() function to execute the native ping utility.\nThe root cause is a flawed input sanitization mechanism. The application employs a denylist approach designed to filter specific shell metacharacters such as space ( ), pipe (|), semicolon (;), and ampersand (&). However, this implementation is insufficient because it fails to filter characters used for command substitution, such as backticks (`) or the $(...) syntax, and fails to restrict alternate field separators like the Internal Field Separator (IFS) or newlines.\nExploitation proceeds through the manipulation of the IpAddr parameter. Since the application fails to validate the format of the IP address and merely checks for blacklisted characters, an attacker can inject a payload utilizing command substitution. For instance, by submitting a payload containing $(whoami) or similar backtick-enclosed commands, the attacker forces the shell to evaluate the injected expression before or during the execution of the primary ping command.\nThe attack flow follows these steps: 1) The attacker authenticates as an administrator and navigates to the diagnostic ping tool. 2) The attacker intercepts the HTTP request to the diagnostic handler. 3) The attacker modifies the IpAddr parameter to include a command substitution payload, effectively bypassing the denylist. 4) The application passes the tainted input directly into the system() call. 5) The shell interprets the injected commands, executing them with root permissions inherited by the web server process.\nBecause the system() function executes the command as root, the payload executes with the highest possible privilege level on the device. Post-exploitation, an attacker can perform arbitrary system calls, read sensitive files (such as configuration files or credentials), or modify the firmware integrity. Furthermore, because the vulnerability allows for arbitrary command execution, the attacker can install persistent backdoors, disable security auditing, or deploy malware, effectively neutralizing the security posture of the router within the network environment."
}