Overview
The world of cybersecurity is constantly evolving, and with it comes a steady stream of new vulnerabilities that threaten the security of our devices. One such vulnerability, identified as CVE-2025-4809, is making headlines due to its critical nature and the potential havoc it could wreak if exploited. This vulnerability has been found in the Tenda AC7 15.03.06.44, a popular router model. The vulnerability stems from a function in the router’s firmware, and if exploited, it could lead to a full system compromise or data leakage, posing severe risks to the users‘ privacy and network security.
Vulnerability Summary
CVE ID: CVE-2025-4809
Severity: Critical, CVSS Severity Score 8.8
Attack Vector: Remote
Privileges Required: None
User Interaction: None
Impact: Potential system compromise and data leakage
Affected Products
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Product | Affected Versions
Tenda AC7 Router | 15.03.06.44
How the Exploit Works
The critical vulnerability lies in the function fromSafeSetMacFilter of the file /goform/setMacFilterCfg. The improper handling of the deviceList argument by this function leads to a stack-based buffer overflow. An attacker can manipulate this argument remotely, causing the overflow and potentially allowing the execution of arbitrary code. This could result in complete system compromise or data leakage.
Conceptual Example Code
This is a
conceptual
example, illustrating how an attacker might exploit the vulnerability. In this case, the attacker sends a specifically crafted HTTP request causing the stack-based buffer overflow:
POST /goform/setMacFilterCfg HTTP/1.1
Host: target.example.com
Content-Type: application/json
{ "deviceList": "A"*5000 }In the above example, “A”*5000 represents a string of 5000 “A” characters, which is far more than the buffer can handle, leading to overflow.
Mitigation Guidance
To mitigate this vulnerability, applying the vendor’s patch is the most effective solution. If the patch is not available or cannot be applied immediately, using a Web Application Firewall (WAF) or an Intrusion Detection System (IDS) can serve as temporary mitigation. These systems can identify and block attempts to exploit this vulnerability, providing an additional layer of protection until the patch can be applied. However, they are not a replacement for timely patching and regular system updates.