CVE-2026-5685
Published: 06 April 2026
Summary
CVE-2026-5685 is a high-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Com (inferred from references). Its CVSS base score is 7.4 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 48.1th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-16 (Memory Protection).
Deeper analysis
CVE-2026-5685 is a stack-based buffer overflow vulnerability affecting the Tenda CX12L router on firmware version 16.03.53.12. The issue resides in the fromAddressNat function within the /goform/addressNat file, where manipulation of the "page" argument triggers the overflow. Published on 2026-04-06, it is associated with CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) and CWE-121 (Stack-based Buffer Overflow).
The vulnerability carries a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H), indicating high severity. Exploitation requires low privileges (PR:L) and can be performed remotely over the network with low complexity and no user interaction. Successful attacks could grant attackers high-impact control, compromising confidentiality, integrity, and availability of the affected device.
Advisories and further details are documented on VulDB (including vuln/355512 and related CTI), a GitHub issue at cve-a/lvdan/issues/3, and the Tenda website. The vendor's site at tenda.com.cn should be consulted for any patches or mitigation guidance, as no specific remediation steps are detailed in the core vulnerability description.
Notable context includes a publicly available exploit, which increases the risk of real-world exploitation attempts against unpatched Tenda CX12L devices.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-19541
Vulnerability details
A vulnerability was identified in Tenda CX12L 16.03.53.12. This affects the function fromAddressNat of the file /goform/addressNat. The manipulation of the argument page leads to stack-based buffer overflow. The attack can be initiated remotely. The exploit is publicly available and…
more
might be used.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Remote stack-based buffer overflow in router web interface (/goform/addressNat) with public exploit directly enables exploitation of public-facing applications.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Directly remediates the stack-based buffer overflow vulnerability by requiring timely identification, reporting, and correction of the flaw in the Tenda CX12L firmware.
Prevents exploitation of the buffer overflow by enforcing validation of the manipulated 'page' argument in the /goform/addressNat endpoint.
Mitigates stack-based buffer overflow exploitation through memory protections such as stack canaries, ASLR, or DEP to block unauthorized code execution.