Home/CVE/Mattermost versions <11 fail to properly restrict access to archived channel search API which allows guest users to disc
CVE

CVE-2025-11776

Mattermost versions <11 fail to properly restrict access to archived channel search API which allows guest users to disc

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.

MEDIUM · CVSS 4.3 EPSS 0.00039
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-863Incorrect Authorization
▤

Affected Products & Versions

1
mattermost server< 11.0.0
▤

Affected Packages

6
Language-ecosystem packages (from OSV) tied to this CVE, with the version that fixes it - the dependency-level detail NVD doesn’t carry.
Go github.com/mattermost/mattermost MODERATE fixed in 5.3.2-0.20250815165020-c8d66301415d
Go github.com/mattermost/mattermost-server MODERATE fixed in 5.3.2-0.20250815165020-c8d66301415d
Go github.com/mattermost/mattermost-server/v5 MODERATE fixed in 5.3.2-0.20250815165020-c8d66301415d
Go github.com/mattermost/mattermost-server/v6 MODERATE fixed in 5.3.2-0.20250815165020-c8d66301415d
Go github.com/mattermost/mattermost/server/v8 MODERATE fixed in 8.0.0-20250815165020-c8d66301415d
Go github.com/mattermost/mattermost/v5
▣

Scoring & Timeline

4.3
MEDIUM · CVSS v3.1 · responsibledisclosure@mattermost.com
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD14 Nov 2025 · 08:15 AM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
SSVC triage · cisa-vulnrichment
Exploitation
none
Automatable
no
Technical impact
partial
SSVC asks the questions that actually drive patch urgency: is it being exploited, can attacks be automated, and how total is the impact.
🔗

References & Sources

1
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://mattermost.com/security-updatesVendor Advisory
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