CVE-2026-71938

Multiple DrayTek VigorSwitch models contain a buffer overflow vulnerability in the switch_lan_gvrp function. The vulnerability is caused by unsafe copying of the portList field into an undersized buffer. A remote attacker can trigger this vulnerability via crafted input, causing a denial of service or potentially executing arbitrary commands. Exploitation requires valid administrative credentials for the device's web management interface.

CVSS v3 7.2 HIGH

7.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.draytek.com/about/security-advisory/multiple-vulnerabilities-in-vigorswitch-series-august-2026/
https://www.vulncheck.com/advisories/draytek-vigorswitch-multiple-models-buffer-overflow-via-switch-lan-gvrp

Configurations

No configuration.

History

12 Oct 2026, 22:10

Type	Values Removed	Values Added
Summary		(es) Múltiples modelos de DrayTek VigorSwitch contienen una vulnerabilidad de desbordamiento de búfer en la función switch_lan_gvrp. La vulnerabilidad es causada por la copia insegura del campo portList en un búfer de tamaño insuficiente. Un atacante remoto puede activar esta vulnerabilidad mediante una entrada manipulada, causando una denegación de servicio o potencialmente ejecutando comandos arbitrarios. La explotación requiere credenciales administrativas válidas para la interfaz de gestión web del dispositivo.

Information

Published : 2026-08-24 18:17

Updated : 2026-10-12 22:10

NVD link : CVE-2026-71938

Mitre link : CVE-2026-71938

CVE.ORG link : CVE-2026-71938

JSON object : View

Products Affected

No product.

CWE

CWE-120

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

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The vulnerability is caused by unsafe copying of the portList field into an undersized buffer. A remote attacker can trigger this vulnerability via crafted input, causing a denial of service or potentially executing arbitrary commands. Exploitation requires valid administrative credentials for the device's web management interface."}, {"lang": "es", "value": "M\u00faltiples modelos de DrayTek VigorSwitch contienen una vulnerabilidad de desbordamiento de b\u00fafer en la funci\u00f3n switch_lan_gvrp. La vulnerabilidad es causada por la copia insegura del campo portList en un b\u00fafer de tama\u00f1o insuficiente. Un atacante remoto puede activar esta vulnerabilidad mediante una entrada manipulada, causando una denegaci\u00f3n de servicio o potencialmente ejecutando comandos arbitrarios. La explotaci\u00f3n requiere credenciales administrativas v\u00e1lidas para la interfaz de gesti\u00f3n web del dispositivo."}], "lastModified": "2026-10-12T22:10:00.247", "sourceIdentifier": "disclosure@vulncheck.com"}