What is the CVSS score of CVE-2026-51844?

CVE-2026-51844 has a CVSS 3.1 base score of 9.8 (Critical). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.4%.

Which versions of Tenda AC7 are affected by CVE-2026-51844?

A critical memory-corruption vulnerability (CVE-2026-51844, CVSS 9.8) in Tenda AC7 router firmware v15.03.06.44 enables unauthenticated remote attack on network edge infrastructure, putting…

How to fix or mitigate CVE-2026-51844?

24 hours: Inventory all Tenda AC7 routers running firmware v15.03.06.44 and immediately restrict administrative interface access via firewall rules; block internet-facing access to the /goform/AdvSetMacMtuWan endpoint. 7 days: Contact Tenda support for patch timeline and interim firmware versions; implement network segmentation to isolate affected routers from critical infrastructure; deploy IDS signatures for /goform/AdvSetMacMtuWan endpoint anomalies. 30 days: Execute hardware replacement with alternative router models or deploy vendor-released patch if available; continuously monitor Tenda security advisories.

Tenda AC7 CVE-2026-51844

EUVD-2026-38050 CRITICAL

Stack-based Buffer Overflow (CWE-121)

2026-06-19 cve@mitre.org

GHSA-g533-f37w-h6w3

Stack Overflow Buffer Overflow Tenda Ac7 Firmware

9.8

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

9.8 CRITICAL

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

vuln.today AI

9.8 CRITICAL

Pre-auth /goform handler reachable over HTTP with no user interaction; stack overflow yields code execution as root on the device, giving full C/I/A impact within the same scope.

3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Primary rating from NVD.

CVSS VectorNVD

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

Analysis Generated

Jun 22, 2026 - 19:08 vuln.today

CVSS changed

Jun 22, 2026 - 18:23 NVD

9.8 (CRITICAL)

CVE Published

Jun 19, 2026 - 17:16 cve.org

UNKNOWN (no severity yet)

DescriptionNVD

Tenda AC7 v15.03.06.44 contains a stack buffer overflow vulnerability in the /goform/AdvSetMacMtuWan interface via the cloneType parameter.

AnalysisAI

Stack buffer overflow in Tenda AC7 router firmware v15.03.06.44 allows remote attackers to corrupt memory via an oversized cloneType parameter sent to the /goform/AdvSetMacMtuWan web interface endpoint. The CVSS 9.8 vector indicates unauthenticated network exploitation with high impact to confidentiality, integrity, and availability. No public exploit identified at time of analysis and the CVE is not listed in CISA KEV.

Technical ContextAI

The Tenda AC7 is a consumer-grade dual-band Wi-Fi router whose web management interface is served by an embedded httpd binary exposing /goform/* CGI-style handlers. The flaw is a classic CWE-121 stack-based buffer overflow: the handler for AdvSetMacMtuWan copies the user-controlled cloneType HTTP parameter into a fixed-size stack buffer without proper length validation, enabling adjacent stack memory (including the saved return address) to be overwritten. This handler is part of the WAN MAC/MTU configuration feature used for ISP MAC cloning, and similar /goform/* endpoints in Tenda devices have historically been a rich source of MIPS-architecture overflow primitives reachable pre-authentication.

RemediationAI

No vendor-released patch identified at time of analysis - the input contains no Tenda advisory URL, fixed firmware version, or KB article, so administrators should monitor https://www.tendacn.com for an AC7 firmware update superseding 15.03.06.44 and apply it once published. As compensating controls, ensure the router's web administration interface is bound to the LAN only and that 'Remote Web Management' / WAN-side HTTP/HTTPS access is disabled (trade-off: loss of off-LAN administration); restrict LAN access to the management IP via client isolation, a dedicated management VLAN, or host-based firewall rules on the admin workstation (trade-off: more complex network setup); change the default admin credentials and disable UPnP to reduce CSRF/SSRF-style internal pivoting risk; and where feasible, replace EOL/EOS Tenda consumer hardware with a supported platform, since /goform/* overflow classes are recurrent in this product line.