CVE-2025-11777 - Vulnerability Details - OpenCVE

Mattermost versions 10.11.x <= 10.11.3, 10.5.x <= 10.5.11 fail to properly validate team membership permissions in the Add Channel Member API which allows users from one team to access user metadata and channel membership information from other teams via the API endpoint

No CVSS v4.0

Attack Vector Network

Attack Complexity High

Privileges Required Low

Scope Unchanged

Confidentiality Impact Low

Integrity Impact None

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable no

Technical Impact partial

No data.

No data.

No data.

No data.

Advisories

No advisories yet.

Fixes

Solution

Update Mattermost to versions 11.0.0, 10.11.4, 10.5.12 or higher.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://mattermost.com/security-updates

History

Thu, 13 Nov 2025 18:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Thu, 13 Nov 2025 17:45:00 +0000

Type	Values Removed	Values Added
Description		Mattermost versions 10.11.x <= 10.11.3, 10.5.x <= 10.5.11 fail to properly validate team membership permissions in the Add Channel Member API which allows users from one team to access user metadata and channel membership information from other teams via the API endpoint
Title		Cross-team channel membership access
Weaknesses		CWE-863
References		https://mattermost.com/security-updates
Metrics		cvssV3_1 `{'score': 3.1, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N'}`

MITRE

Status: PUBLISHED

Assigner: Mattermost

Published: 2025-11-13T17:32:03.975Z

Updated: 2025-11-13T18:01:46.459Z

Reserved: 2025-10-15T11:37:25.782Z

Link: CVE-2025-11777

Vulnrichment

Updated: 2025-11-13T18:01:42.725Z

NVD

Status : Received

Published: 2025-11-13T18:15:49.393

Modified: 2025-11-13T18:15:49.393

Link: CVE-2025-11777

Redhat

No data.

OpenCVE Enrichment

No data.

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