CVE-2026-2458 - Vulnerability Details - OpenCVE

Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to properly validate team membership when searching channels which allows a removed team member to enumerate all public channels within a private team via the channel search API endpoint.. Mattermost Advisory ID: MMSA-2025-00568

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

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.

The EPSS score is 0.00025.

Exploitation none

Automatable no

Technical Impact partial

No data.

No data.

No data.

No data.

References

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

History

Mon, 16 Mar 2026 14:15:00 +0000

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

Mon, 16 Mar 2026 11:45:00 +0000

Type	Values Removed	Values Added
Description		Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to properly validate team membership when searching channels which allows a removed team member to enumerate all public channels within a private team via the channel search API endpoint.. Mattermost Advisory ID: MMSA-2025-00568
Title		Unauthorized channel enumeration in private teams after member removal
Weaknesses		CWE-862
References		https://mattermost.com/security-updates
Metrics		cvssV3_1 `{'score': 4.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N'}`

MITRE

Status: PUBLISHED

Assigner: Mattermost

Published: 2026-03-16T11:27:49.310Z

Updated: 2026-03-16T13:49:57.631Z

Reserved: 2026-02-13T11:08:09.268Z

Link: CVE-2026-2458

Vulnrichment

Updated: 2026-03-16T13:44:13.623Z

NVD

Status : Awaiting Analysis

Published: 2026-03-16T14:19:29.543

Modified: 2026-03-16T14:53:07.390

Link: CVE-2026-2458

Redhat

No data.

OpenCVE Enrichment

No data.

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