CVE-2025-8679

In ExtremeGuest Essentials before 25.5.0, captive-portal may permit unauthorized access via manual brute-force procedure. Under certain ExtremeGuest Essentials captive-portal SSID configurations, repeated manual login attempts may allow an unauthenticated device to be marked as authenticated and obtain network access. Client360 logs may display the client MAC as the username despite no MAC-authentication being enabled.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://extreme-networks.my.site.com/ExtrArticleDetail?an=000130289	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:extremenetworks:extremeguest_essentials:*:*:*:*:*:*:*:*

History

12 Oct 2026, 15:10

Type	Values Removed	Values Added
Summary		(es) En ExtremeGuest Essentials antes de 25.5.0, el portal cautivo puede permitir acceso no autorizado a través de un procedimiento manual de fuerza bruta. Bajo ciertas configuraciones de SSID de portal cautivo de ExtremeGuest Essentials, intentos de inicio de sesión manuales repetidos pueden permitir que un dispositivo no autenticado sea marcado como autenticado y obtenga acceso a la red. Los registros de Client360 pueden mostrar la MAC del cliente como el nombre de usuario a pesar de que no haya autenticación MAC habilitada.

Information

Published : 2025-10-01 18:15

Updated : 2026-10-12 15:10

NVD link : CVE-2025-8679

Mitre link : CVE-2025-8679

CVE.ORG link : CVE-2025-8679

JSON object : View

Products Affected

extremenetworks

extremeguest_essentials

CWE

CWE-307

Improper Restriction of Excessive Authentication Attempts

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