Mattermost up to 10.11.9/11.1.2/11.2.1 Team Membership channel_mentions authorization

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.2$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic has been found in Mattermost up to 10.11.9/11.1.2/11.2.1. Affected is an unknown function of the component Team Membership Handler. Performing a manipulation of the argument channel_mentions results in authorization. This vulnerability is identified as CVE-2025-14350. The attack can be initiated remotely. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Mattermost up to 10.11.9/11.1.2/11.2.1. It has been classified as problematic. This affects some unknown processing of the component Team Membership Handler. The manipulation of the argument channel_mentions with an unknown input leads to a authorization vulnerability. CWE is classifying the issue as CWE-862. The product does not perform an authorization check when an actor attempts to access a resource or perform an action. This is going to have an impact on confidentiality. The summary by CVE is:

Mattermost versions 11.1.x <= 11.1.2, 10.11.x <= 10.11.9, 11.2.x <= 11.2.1 fail to properly validate team membership when processing channel mentions which allows authenticated users to determine the existence of teams and their URL names via posting channel shortlinks and observing the channel_mentions property in the API response. Mattermost Advisory ID: MMSA-2025-00563

The weakness was released by Harrison Healey. It is possible to read the advisory at mattermost.com. This vulnerability is uniquely identified as CVE-2025-14350 since 12/09/2025. The exploitability is told to be easy. It is possible to initiate the attack remotely. Technical details of the vulnerability are known, but there is no available exploit.

Upgrading to version 10.11.10, 11.1.3, 11.2.2 or 11.3.0 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2025-206980). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.2

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 4.3
CNA Vector (Mattermost): 🔒

CVSSv2info

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

Exploitinginfo

Class: Authorization
CWE: CWE-862 / CWE-863 / CWE-285
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: Mattermost 10.11.10/11.1.3/11.2.2/11.3.0

Timelineinfo

12/09/2025 CVE reserved
02/16/2026 +69 days Advisory disclosed
02/16/2026 +0 days VulDB entry created
02/20/2026 +4 days VulDB entry last update

Sourcesinfo

Advisory: mattermost.com
Researcher: Harrison Healey
Status: Confirmed

CVE: CVE-2025-14350 (🔒)
GCVE (CVE): GCVE-0-2025-14350
GCVE (VulDB): GCVE-100-346191
EUVD: 🔒

Entryinfo

Created: 02/16/2026 15:58
Updated: 02/20/2026 09:54
Changes: 02/16/2026 15:58 (65), 02/17/2026 18:10 (1), 02/20/2026 09:54 (1)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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