Overview
This article provides a detailed analysis of CVE-2025-65223, a buffer overflow vulnerability affecting Tenda AC21 routers, specifically version V16.03.08.16. This vulnerability could allow a remote attacker to potentially execute arbitrary code on the device.
Technical Details
CVE-2025-65223 is a buffer overflow vulnerability located in the /goform/saveParentControlInfo endpoint of the Tenda AC21 router’s firmware. The vulnerability is triggered by an overly long input to the urls parameter. Because the firmware does not properly validate the length of the input, a specially crafted request with an excessive urls value can overwrite adjacent memory regions, leading to potential code execution.
CVSS Analysis
Currently, the CVSS score for CVE-2025-65223 is marked as N/A. This is either because the vulnerability is newly discovered, or the severity has not yet been formally assessed. A full CVSS analysis should be performed when the data is available, and the score could range from Low to Critical, depending on the exploitability and impact.
Possible Impact
If successfully exploited, this buffer overflow vulnerability could allow a remote attacker to:
- Execute arbitrary code on the router.
- Gain unauthorized access to the router’s configuration.
- Potentially compromise the entire network connected to the router.
- Cause a denial-of-service (DoS) condition.
Mitigation and Patch Steps
To mitigate the risk of CVE-2025-65223, the following steps are recommended:
- Update Firmware: Check the Tenda website for a firmware update that addresses this vulnerability. Apply the update as soon as it becomes available.
- Disable Remote Management: If possible, disable remote management of the router to reduce the attack surface.
- Network Segmentation: Segment your network to limit the impact of a potential compromise.
- Monitor Network Traffic: Monitor network traffic for suspicious activity that could indicate an attempted exploitation.
References
- Vulnerability Report – GitHub
- Tenda Official Website
- NIST NVD – CVE-2025-65223 (This will be the official link once published)
