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

15 Jan 2026, 02:17

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 9.8
First Time		Extremenetworks Extremenetworks extremeguest Essentials
CPE		cpe:2.3:a:extremenetworks:extremeguest_essentials::::::::
References	~~() https://extreme-networks.my.site.com/ExtrArticleDetail?an=000130289 -~~	() https://extreme-networks.my.site.com/ExtrArticleDetail?an=000130289 - Vendor Advisory

01 Oct 2025, 18:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2025-10-01 18:15

Updated : 2026-01-15 02:17

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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