ExtremeGuest Essentials 25.4.0 Captive-Portal excessive authentication

CVSS Meta Temp Score
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CTI Interest Score
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6.4$0-$5k0.00

Summaryinfo

A vulnerability labeled as problematic has been found in ExtremeGuest Essentials 25.4.0. Impacted is an unknown function of the component Captive-Portal. Such manipulation leads to excessive authentication. This vulnerability is uniquely identified as CVE-2025-8679. The attack can only be initiated within the local network. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in ExtremeGuest Essentials 25.4.0. It has been rated as problematic. Affected by this issue is an unknown part of the component Captive-Portal. The manipulation with an unknown input leads to a excessive authentication vulnerability. Using CWE to declare the problem leads to CWE-307. The product does not implement sufficient measures to prevent multiple failed authentication attempts within a short time frame, making it more susceptible to brute force attacks. Impacted is confidentiality. CVE summarizes:

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.

The advisory is shared for download at extreme-networks.my.site.com. This vulnerability is handled as CVE-2025-8679 since 08/06/2025. The exploitation is known to be difficult. The attack needs to be done within the local network. No form of authentication is required for exploitation. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1110.001.

Upgrading to version 25.5.0 eliminates this vulnerability.

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Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.4

VulDB Base Score: 3.1
VulDB Temp Score: 3.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Excessive authentication
CWE: CWE-307 / CWE-799 / CWE-400
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Essentials 25.5.0

Timelineinfo

08/06/2025 CVE reserved
10/02/2025 +57 days Advisory disclosed
10/02/2025 +0 days VulDB entry created
01/15/2026 +105 days VulDB entry last update

Sourcesinfo

Advisory: extreme-networks.my.site.com
Status: Confirmed

CVE: CVE-2025-8679 (🔒)
GCVE (CVE): GCVE-0-2025-8679
GCVE (VulDB): GCVE-100-326672

Entryinfo

Created: 10/02/2025 08:07
Updated: 01/15/2026 04:41
Changes: 10/02/2025 08:07 (67), 01/15/2026 04:41 (11)
Complete: 🔍
Cache ID: 216::103

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