Cyber Posture

CVE-2025-70646

HighPublic PoC

Published: 21 January 2026

Published
21 January 2026
Modified
26 January 2026
KEV Added
Patch
CVSS Score 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0008 22.4th percentile
Risk Priority 15 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-70646 is a high-severity Stack-based Buffer Overflow (CWE-121) vulnerability in Tenda Ax1803 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 22.4th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190) and 1 other technique.
Threat & Defense Details

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.
T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
Why these techniques?

Remote unauthenticated stack overflow in public-facing router firmware directly enables T1190 exploitation and T1499.004 DoS via application/system exploitation.

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

NVD Description

Tenda AX1803 v1.0.0.1 was discovered to contain a stack overflow in the security parameter of the sub_72290 function. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted request.

Deeper analysisAI

CVE-2025-70646 is a stack overflow vulnerability (CWE-121) in the security parameter of the sub_72290 function within Tenda AX1803 firmware version v1.0.0.1. This flaw enables attackers to trigger a Denial of Service (DoS) condition through a specially crafted network request. The vulnerability was publicly disclosed on January 21, 2026, and carries a CVSS v3.1 base score of 7.5, reflecting its high severity due to the potential for remote disruption without authentication.

The attack scenario is straightforward and highly accessible: unauthenticated attackers with network access to the affected device (AV:N/AC:L/PR:N/UI:N) can send a malicious request to the vulnerable function, causing a stack overflow that crashes the device and disrupts service availability (A:H). No user interaction or privileges are required, making it suitable for remote exploitation by any adversary on the same network or exposed to the internet. Successful exploitation results solely in DoS, with no impact on confidentiality or integrity (C:N/I:N).

Mitigation details and further technical analysis are provided in the referenced advisory at https://github.com/0-fool/VulnbyCola/blob/main/Tenda/AX-1803/5/1.md. Security practitioners should consult this source for reproduction steps, patch information if available, and recommended remediation actions, such as firmware updates or network segmentation.

Details

CWE(s)

Affected Products

tenda
ax1803 firmware
1.0.0.1

CVEs Like This One

CVE-2025-70651Same product: Tenda Ax1803
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CVE-2025-7598Same product: Tenda Ax1803
CVE-2025-7597Same product: Tenda Ax1803
CVE-2025-70746Same vendor: Tenda
CVE-2025-29121Same vendor: Tenda
CVE-2025-70656Same vendor: Tenda
CVE-2025-29214Same vendor: Tenda
CVE-2025-70747Same vendor: Tenda

References