CVE-2025-71027
Published: 13 January 2026
Summary
CVE-2025-71027 is a high-severity Out-of-bounds Write (CWE-787) vulnerability in Tenda Ax3 Firmware. Its CVSS base score is 7.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 26.4th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-16 (Memory Protection).
Deeper analysis
CVE-2025-71027 is a stack overflow vulnerability affecting the Tenda AX-3 router running firmware version v16.03.12.10_CN. The issue resides in the wanMTU2 parameter of the fromAdvSetMacMtuWan function, which can be triggered by a specially crafted request. Published on 2026-01-13, it has a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) and is associated with CWEs-787 (Out-of-bounds Write) and CWE-121 (Stack-based Buffer Overflow).
Unauthenticated attackers with network access can exploit this vulnerability by sending a malicious request to the affected function, resulting in a denial-of-service condition that crashes the device. No user interaction or privileges are required, and the attack has low complexity, making it accessible to remote adversaries targeting exposed Tenda AX-3 routers.
References for this CVE point to GitHub repositories at https://github.com/0-fool/VulnbyCola/blob/main/Tenda/AX-3/8/1.md, which document the vulnerability discovery and likely include technical details or proof-of-concept information. No vendor advisories or patches are specified in the available data.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-2268
Vulnerability details
Tenda AX-3 v16.03.12.10_CN was discovered to contain a stack overflow in the wanMTU2 parameter of the fromAdvSetMacMtuWan function. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted request.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Remote unauthenticated stack overflow in router web interface (fromAdvSetMacMtuWan/wanMTU2) directly enables T1190 (Exploit Public-Facing Application) and T1499.004 (Application or System Exploitation) to achieve DoS.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Validates the wanMTU2 parameter in crafted requests to prevent stack overflows leading to DoS.
Implements memory protections like stack canaries and non-executable memory to mitigate exploitation of the stack-based buffer overflow.
Remediates the specific stack overflow flaw in the fromAdvSetMacMtuWan function through timely patching and testing.