CVE-2025-11776

Guest user can discover archived public channels

Published Nov 14, 2025 CVSS 3.1 · 4.3 Medium EPSS < 1% KEV · Not listed
Description
Mattermost versions <11 fail to properly restrict access to archived channel search API which allows guest users to discover archived public channels via the `/api/v4/teams/{team_id}/channels/search_archived` endpoint

Remediation

Vendor Solution

Update Mattermost to versions 11.0.0 or higher.

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-j6gg-r5jc-47cm Mattermost fails to properly restrict access to archived channel search API
References
History
Type Values Removed Values Added
First Time appeared Mattermost mattermost Server
CPEs cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
Vendors & Products Mattermost mattermost Server
Type Values Removed Values Added
First Time appeared Mattermost
Mattermost mattermost
Vendors & Products Mattermost
Mattermost mattermost
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Mattermost versions <11 fail to properly restrict access to archived channel search API which allows guest users to discover archived public channels via the `/api/v4/teams/{team_id}/channels/search_archived` endpoint
Title Guest user can discover archived public channels
Weaknesses CWE-863
References
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'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
Mattermost
Published
Updated
Nov 14, 2025, 3:49 PM
Reserved
Oct 15, 2025, 11:35 AM
Status
Analyzed
Published
Nov 14, 2025, 8:15 AM
Modified
Oct 19, 2026, 1:10 PM