CVE-2026-58147 in T-Mobile 5G Box IDU
Summary
by MITRE • 09/17/2026
WNC T-Mobile 5G Box IDU router contains an OS command injection vulnerability in the portal.cgi component's password change functionality. The application improperly neutralizes special elements in the http_passwd_hidden and http_passwdConfirm_hidden parameters, allowing an authenticated attacker to execute arbitrary commands on the underlying operating system with root privileges.This issue has been fixed in firmware version 1.1.0.651412
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Analysis
by VulDB Data Team • 09/17/2026
The vulnerability identified within the WNC T-Mobile 5G Box IDU router represents a critical security flaw located specifically within the portal.cgi component, which handles administrative interface operations for the device. This particular issue manifests during the password change functionality of the web-based management console. The root cause lies in the improper neutralization or sanitization of special characters and shell metacharacters embedded within two specific HTTP parameters: http_passwd_hidden and http_passwdConfirm_hidden. In a secure implementation, user-supplied input destined for system-level operations must be strictly validated against an allowlist of acceptable characters to prevent injection attacks. However, in this firmware version, the application fails to adequately filter or escape these special elements before passing them to underlying shell commands or interpreters that process the password update request.
This lack of proper input validation creates a classic OS command injection vulnerability, which is formally categorized under CWE-78: Improper Neutralization of Special Elements used in an Operating System Command (OS Command Injection). Because the vulnerable parameters are processed by the backend system without sufficient scrutiny, an attacker can inject arbitrary shell commands into the password fields. For instance, by appending a semicolon or pipe character followed malicious code to one of these hidden input values, the injected payload becomes part of the executed command string on the router's operating system. This flaw effectively bypasses any intended logical separation between user data and executable instructions, allowing external inputs to be interpreted as commands by the host environment.
The operational impact of this vulnerability is severe due to the privilege level granted to the compromised process. The portal.cgi component typically runs with elevated privileges, often root access, which controls all aspects of the router's firmware and network configuration. Consequently, an authenticated attacker who possesses valid administrative credentials for the web interface can exploit this flaw to execute arbitrary commands on the underlying operating system with full root privileges. This capability allows the adversary to perform a wide range of malicious actions, including but not limited to installing persistent backdoors, exfiltrating sensitive data such as network keys and user credentials, modifying firewall rules to expose internal networks, or completely compromising the integrity of the device for use in botnets or further lateral movement within an enterprise environment.
From a threat intelligence perspective, this exploitation technique aligns with MITRE ATT&CK techniques related to Command and Scripting Interpreter abuse, specifically T1059 which covers various scripting languages used by adversaries to execute commands on target systems. The ability to escalate privileges via command injection is particularly dangerous in Internet of Things (IoT) devices like 5G routers because they often serve as gateways between external networks and sensitive internal infrastructure. Once the router is compromised, it can be used as a pivot point for attacks against other devices on the local network that may have weaker security postures or lack direct internet-facing exposure.
To mitigate this risk, organizations utilizing WNC T-Mobile 5G Box IDU routers must immediately apply the firmware update to version 1.1.0.651412 or later, as this release contains the necessary code fixes for input validation in the portal.cgi module. In environments where immediate patching is not feasible due to operational constraints, temporary mitigations should be implemented at the network perimeter level. This includes restricting access to the router's management interface exclusively through trusted IP addresses using firewall rules and ensuring that administrative ports are not exposed to untrusted networks such as the public internet. Additionally, enforcing strong password policies can reduce the risk of credential theft which is a prerequisite for exploiting this authenticated vulnerability, although it does not eliminate the technical flaw itself. Regular monitoring of network traffic for anomalous outbound connections from the router can also help in detecting potential exploitation attempts or post-compromise activity resulting from successful attacks on unpatched systems.