Overview
CVE-2025-65222 details a buffer overflow vulnerability found in the Tenda AC21 router, specifically version V16.03.08.16. This vulnerability exists within the /goform/SetSysAutoRebbotCfg endpoint and is triggered via the rebootTime parameter. Successful exploitation could lead to arbitrary code execution, denial of service, or other potentially malicious outcomes.
Technical Details
The vulnerability lies within the handling of the rebootTime parameter in the /goform/SetSysAutoRebbotCfg endpoint. Insufficient input validation allows an attacker to provide a string larger than the allocated buffer size. This overflow can overwrite adjacent memory regions, potentially allowing for the execution of attacker-controlled code. The affected firmware version is V16.03.08.16 for the Tenda AC21 router.
An attacker could exploit this vulnerability by crafting a malicious HTTP request containing an oversized rebootTime parameter. This request could then be sent to the vulnerable router via the web interface.
CVSS Analysis
Currently, the CVSS score for CVE-2025-65222 is N/A, indicating it has not yet been formally assessed. However, given the nature of buffer overflow vulnerabilities, especially in network devices, it is likely to be assigned a high severity score once evaluated.
Possible Impact
The potential impact of this vulnerability is significant. Successful exploitation could lead to:
- Arbitrary Code Execution: An attacker could execute malicious code on the router, potentially gaining complete control over the device.
- Denial of Service (DoS): The buffer overflow could crash the router, preventing legitimate users from accessing the network.
- Data Theft: An attacker could access and steal sensitive data stored on the router or transmitted through the network.
- Malware Installation: The router could be compromised and used as a platform to spread malware to other devices on the network.
Mitigation or Patch Steps
Currently, there is no official patch available from Tenda for this vulnerability. It is crucial to take the following steps to mitigate the risk:
- Monitor Tenda’s website for firmware updates: Regularly check the official Tenda website for updated firmware that addresses this vulnerability.
- Disable Remote Administration: If possible, disable remote administration of the router to limit the attack surface.
- Restrict Access to the Web Interface: Only allow trusted devices within your network to access the router’s web interface.
- Use a Strong Password: Ensure you are using a strong, unique password for your router’s web interface.
- Consider alternative router solutions: If no patch is released, you might need to consider a more secure router with up-to-date security support.
References
GitHub – Madgeaaaaa: Vulnerability Report
Tenda Official Website
NIST NVD – CVE-2025-65222
