CVE-2026-71942

Multiple DrayTek VigorSwitch models contain a buffer overflow vulnerability in the mail_mailalert function. The vulnerability is caused by concatenating multiple smtpReceiver email addresses into a fixed-size buffer without checking the remaining buffer size. 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-mail-mailalert

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 mail_mailalert. La vulnerabilidad es causada por la concatenación de múltiples direcciones de correo electrónico smtpReceiver en un búfer de tamaño fijo sin verificar el tamaño restante del búfer. Un atacante remoto puede activar esta vulnerabilidad a través de 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-2026-71942

Mitre link : CVE-2026-71942

CVE.ORG link : CVE-2026-71942

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 concatenating multiple smtpReceiver email addresses into a fixed-size buffer without checking the remaining buffer size. 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 mail_mailalert. La vulnerabilidad es causada por la concatenaci\u00f3n de m\u00faltiples direcciones de correo electr\u00f3nico smtpReceiver en un b\u00fafer de tama\u00f1o fijo sin verificar el tama\u00f1o restante del b\u00fafer. Un atacante remoto puede activar esta vulnerabilidad a trav\u00e9s de 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"}