CVE-2026-3870

A buffer overflow vulnerability in the UPnP AddPortMapping() command in Zyxel VMG4005-B50B firmware versions through 5.13(ABRL.5.4)C0 could allow an adjacent attacker to trigger a temporary denial-of-service (DoS) condition affecting the UPnP function of the affected device.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-buffer-overflow-vulnerabilities-in-the-upnp-function-of-certain-4g-lte-5g-nr-cpe-and-dsl-ethernet-cpe-06-02-2026

Configurations

No configuration.

History

22 Jul 2026, 19:10

Type	Values Removed	Values Added
Summary		(es) Una vulnerabilidad de desbordamiento de búfer en el comando UPnP AddPortMapping() en las versiones de firmware de Zyxel VMG4005-B50B hasta la 5.13(ABRL.5.4)C0 podría permitir a un atacante adyacente activar una condición temporal de denegación de servicio (DoS) que afecta a la función UPnP del dispositivo afectado.

02 Jun 2026, 03:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-02 03:16

Updated : 2026-07-22 19:10

NVD link : CVE-2026-3870

Mitre link : CVE-2026-3870

CVE.ORG link : CVE-2026-3870

JSON object : View

Products Affected

No product.

CWE

CWE-120

Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

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