Cyber Posture

CVE-2026-4043

HighPublic PoC

Published: 12 March 2026

Published
12 March 2026
Modified
02 April 2026
KEV Added
Patch
CVSS Score 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0011 28.3th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-4043 is a high-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Tenda I12 Firmware. Its CVSS base score is 8.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 28.3th 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).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190) and 1 other technique. What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

Flaw remediation directly addresses the stack-based buffer overflow by applying vendor patches or firmware updates to eliminate the vulnerability in the formwrlSSIDget function.

prevent

Information input validation enforces bounds checking on the index argument in /goform/wifiSSIDget, preventing the crafted input from triggering the buffer overflow.

prevent

Memory protection mechanisms like stack canaries, ASLR, and DEP prevent exploitation of the stack-based buffer overflow for arbitrary code execution even if invalid input is processed.

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
Why these techniques?

Stack buffer overflow in router web form handler (/goform/wifiSSIDget) enables remote exploitation of public-facing application (T1190) with authenticated low-priv access and directly supports privilege escalation to arbitrary code execution (T1068).

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD Description

A security vulnerability has been detected in Tenda i12 1.0.0.6(2204). The impacted element is the function formwrlSSIDget of the file /goform/wifiSSIDget. Such manipulation of the argument index leads to stack-based buffer overflow. The attack may be launched remotely. The exploit…

more

has been disclosed publicly and may be used.

Deeper analysisAI

CVE-2026-4043 is a stack-based buffer overflow vulnerability in the Tenda i12 router running firmware version 1.0.0.6(2204). The issue affects the formwrlSSIDget function within the /goform/wifiSSIDget file, where manipulation of the index argument triggers the overflow. This flaw, associated with CWE-119, CWE-121, and CWE-787, was published on 2026-03-12 and 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 due to its potential for significant impact.

The vulnerability can be exploited remotely by an attacker with low privileges (PR:L), requiring network access and low complexity with no user interaction needed. By sending a crafted request manipulating the index argument, the attacker can trigger the stack-based buffer overflow, potentially leading to high confidentiality, integrity, and availability impacts, such as arbitrary code execution on the affected device.

Advisories and additional details are available through references including a GitHub issue at https://github.com/Jimi-Lab/cve/issues/3 disclosing a public exploit, VulDB entries at https://vuldb.com/?ctiid.350655, https://vuldb.com/?id.350655, and https://vuldb.com/?submit.769464, and the vendor site at https://www.tenda.com.cn/. The exploit has been publicly disclosed and may be used, but specific patch or mitigation guidance is not detailed in the core vulnerability information.

Details

CWE(s)

Affected Products

tenda
i12 firmware
1.0.0.6\(2204\)

CVEs Like This One

CVE-2026-4042Same product: Tenda I12
CVE-2026-4041Same product: Tenda I12
CVE-2026-5609Same product: Tenda I12
CVE-2025-29149Same product: Tenda I12
CVE-2025-25678Same product: Tenda I12
CVE-2025-25676Same product: Tenda I12
CVE-2025-25679Same product: Tenda I12
CVE-2026-5849Same product: Tenda I12
CVE-2026-3974Same vendor: Tenda
CVE-2026-4008Same vendor: Tenda

References