Overview
A critical vulnerability has been discovered in Tenda AC6 15.03.05.16, a widely-used router firmware. The vulnerability, classified as CVE-2025-5854, resides in the function fromadvsetlanip of the file /goform/AdvSetLanip. This vulnerability is particularly concerning as it allows the potential for remote attackers to overflow the buffer by manipulating the argument lanMask. The implications of this vulnerability are severe, ranging from system compromise to potential data leakage. The vulnerability’s severity and possible widespread impact underscore the importance of immediate attention and mitigation.
Vulnerability Summary
CVE ID: CVE-2025-5854
Severity: Critical (CVSS: 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 AC6 | 15.03.05.16
How the Exploit Works
The vulnerability resides in the fromadvsetlanip function of the file /goform/AdvSetLanip. This function does not adequately validate the lanMask argument, rendering it susceptible to buffer overflow attacks. A remote attacker can exploit this vulnerability by sending specially crafted inputs to overflow the buffer, which can lead to arbitrary code execution or denial of service.
Conceptual Example Code
This conceptual example demonstrates how a remote attacker might exploit this vulnerability. The malicious payload is designed to overflow the buffer and potentially execute arbitrary code.
POST /goform/AdvSetLanip HTTP/1.1
Host: target.example.com
Content-Type: application/x-www-form-urlencoded
lanMask=255.255.255.0&lanIp=192.168.1.1&lanMask=AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA...In this example, the ‘A’s represent excess input designed to overflow the buffer.
Mitigation
Users are advised to apply the vendor patch as soon as it is available to mitigate this vulnerability. In the interim, users can deploy Web Application Firewalls (WAFs) or Intrusion Detection Systems (IDS) as temporary mitigation measures. These solutions can detect and block malicious requests attempting to exploit this vulnerability.
Conclusion
The discovery of the CVE-2025-5854 vulnerability in Tenda AC6 15.03.05.16 highlights the ongoing importance of thorough software testing, regular patch management, and proactive security measures. As cyber threats continue to evolve, it remains crucial for organizations and individuals to stay informed, vigilant, and prepared.