Cyber Posture

CVE-2025-69766

CriticalPublic PoC

Published: 21 January 2026

Published
21 January 2026
Modified
26 January 2026
KEV Added
—
Patch
—
CVSS Score 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0045 63.9th percentile
Risk Priority 20 60% EPSS · 20% KEV · 20% CVSS

Description

Tenda AX3 firmware v16.03.12.11 contains a stack-based buffer overflow in the formGetIptv function due to improper handling of the citytag stack buffer, which may result in memory corruption and remote code execution.

Mitigating Controls (NIST 800-53 r5)AI

SI-10 Information Input Validation good match
prevent

Directly addresses the improper handling of the citytag input in formGetIptv by enforcing input validation at critical entry points to prevent stack buffer overflows.

SI-16 Memory Protection good match
prevent

Implements memory protection mechanisms like stack canaries and non-executable stacks to mitigate exploitation of stack-based buffer overflows leading to memory corruption.

SI-2 Flaw Remediation good match
prevent

Mandates identification, reporting, and correction of flaws such as this buffer overflow in Tenda AX3 firmware to prevent remote code execution.

Security SummaryAI

CVE-2025-69766, published on 2026-01-21, is a stack-based buffer overflow vulnerability in the formGetIptv function of Tenda AX3 firmware version v16.03.12.11. The flaw stems from improper handling of the citytag stack buffer, which can lead to memory corruption and remote code execution. It is classified under CWE-121 and carries a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).

Unauthenticated attackers with network access can exploit this vulnerability due to its low attack complexity and lack of required privileges or user interaction. Successful exploitation enables remote code execution on the targeted device, resulting in high-impact compromises to confidentiality, integrity, and availability.

Advisories providing further details on the vulnerability are available at the following references: https://river-brow-763.notion.site/Tenda-AX3-Buffer-Overflow-in-formGetIptv-2c9a595a7aef8043a091e6722b8e255a and https://river-brow-763.notion.site/Tenda-AX3-Buffer-Overflow-in-formGetIptv-2c9a595a7aef8043a091e6722b8e255a?source=copy_link.

Details

CWE(s)
CWE-121

Affected Products

tenda
ax3 firmware
16.03.12.11

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.
attack.mitre.org →
Why these techniques?

Unauthenticated stack-based buffer overflow in router firmware enables remote code execution on a public-facing application.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

References