CVE-2025-4007: Critical Stack-Based Buffer Overflow Vulnerability in Tenda W12 and i24

Overview

A severe vulnerability, classified as critical, has been identified in Tenda W12 and i24, two popular devices that many businesses and individuals use for networking purposes. This cyber vulnerability, officially designated as CVE-2025-4007, impacts version 3.0.0.4(2887)/3.0.0.5(3644) of these devices. It is centered around the function cgidhcpsCfgSet of the file /goform/modules of the httpd component, leading to stack-based buffer overflow. This vulnerability is especially concerning because the exploit has been disclosed publicly, opening a potential door for cybercriminals to launch attacks remotely, compromising systems and leaking sensitive data.

Vulnerability Summary

CVE ID: CVE-2025-4007
Severity: Critical, with a CVSS Severity Score of 8.8
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: Potential system compromise or data leakage

Affected Products

Product | Affected Versions

Tenda W12 | 3.0.0.4(2887)/3.0.0.5(3644)
Tenda i24 | 3.0.0.4(2887)/3.0.0.5(3644)

How the Exploit Works

The vulnerability arises from the manipulation of the ‘json’ argument in the function ‘cgidhcpsCfgSet’ of the file ‘/goform/modules’ in the ‘httpd’ component. The manipulated ‘json’ argument leads to a stack-based buffer overflow. This overflow condition gives an attacker the ability to overwrite the intended data of the buffer, leading to the execution of arbitrary code, crashing the system, or causing a denial of service.

Conceptual Example Code

Below is a conceptual example of how the vulnerability might be exploited. This is a sample HTTP request.

POST /goform/modules HTTP/1.1
Host: target-Tenda-device.com
Content-Type: application/json
{
"json": "A"*5000 // Overly long string triggering buffer overflow
}

In this example, the overly long string “A”*5000 is sent as the ‘json’ argument. This string is long enough to trigger a buffer overflow, potentially allowing an attacker to execute arbitrary code or crash the system.
Please note that this example is conceptual and not meant to be used for malicious activities. Always follow ethical cybersecurity practices.