mattermost Vulnerability Advisory Catalog

Total 602 security vulnerabilities recorded for mattermost software and firmware.

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CVE-2026-3471 MEDIUM
Component: mattermost_desktop

Mattermost Desktop App versions <=6.1 6.0.1 5.4.13.0 fail to prevent an invalid URL from loading in a pop-up window in the Mattermost Desktop App whic...

📅 2026-05-18
CVSS 6.5 Dossier →
CVE-2026-3117 MEDIUM
Component: mattermost_server

Mattermost Plugins versions <=11.5 11.1.5 10.13.11 11.3.4.0 fail to properly check for permissions when processing commands in the Gitlab plugin which...

📅 2026-05-18
CVSS 6.5 Dossier →
Component: mattermost_server

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 Fail to enforce slash command trigger-word uniqueness during command updat...

📅 2026-05-18
CVSS 4.3 Dossier →
CVE-2026-6342 MEDIUM
Component: mattermost_server

Mattermost Plugins versions <=11.5 11.1.5 10.13.11 11.3.4.0 fail to appropriately check for valid namespaces which allows plugin users to create subsc...

📅 2026-05-18
CVSS 4.3 Dossier →
CVE-2026-6341 MEDIUM
Component: mattermost_server

Mattermost Plugins versions <=11.5 11.1.5 10.13.11 11.3.4.0 fail to have API-level checks on which groups the user can create issues or attach comment...

📅 2026-05-18
CVSS 4.3 Dossier →
CVE-2026-6340 MEDIUM
Component: mattermost_server

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to validate 7zip archive structure before processing which allows an ...

📅 2026-05-18
CVSS 4.3 Dossier →
Component: mattermost_server

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13 fail to enforce client identity binding during the OAuth authorization code redemption flow ...

📅 2026-05-18
CVSS 3.1 Dossier →
Component: mattermost_server

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13 fail to validate that the RefreshedToken differs from the original invite token during remot...

📅 2026-05-18
CVSS 3.7 Dossier →
CVE-2026-3637 MEDIUM
Component: mattermost_server

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to check the create_post channel permission during post edit operatio...

📅 2026-05-18
CVSS 4.3 Dossier →
Component: mattermost_server

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13 fail to escape some variables that could contain malicious content during error page composi...

📅 2026-05-18
CVSS 3.8 Dossier →
CVE-2026-2325 MEDIUM
Component: mattermost_server

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to limit the size of the request body on the start meeting API endpoi...

📅 2026-05-18
CVSS 4.3 Dossier →
Component: mattermost_server

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to validate that a remote cluster has access to a channel before proc...

📅 2026-05-18
CVSS 4.3 Dossier →
CVE-2026-4054 MEDIUM
Component: mattermost_server

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 Fail to validate the response body of proxied images, which allows a remot...

📅 2026-05-15
CVSS 4.3 Dossier →
Component: mattermost_server

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13 fail to enforce the PostEditTimeLimit on non-message post fields which allows an authenticat...

📅 2026-05-15
CVSS 3.1 Dossier →
CVE-2026-3590 MEDIUM
Component: mattermost_server

Mattermost versions 10.11.x <= 10.11.12, 11.5.x <= 11.5.0, 11.4.x <= 11.4.2, 11.3.x <= 11.3.2 fail to enforce atomic single-use consumption of guest m...

📅 2026-04-15
CVSS 6.5 Dossier →
Component: mattermost_server

Mattermost versions 10.11.x <= 10.11.12, 11.5.x <= 11.5.0, 11.4.x <= 11.4.2, 11.3.x <= 11.3.2 fail to validate CSRF tokens on an authentication endpoi...

📅 2026-04-15
CVSS 6.8 Dossier →
Component: mattermost_server

Mattermost versions 10.11.x <= 10.11.12 fail to validate whether users were correctly owned by the correct Connected Workspace which allows a maliciou...

📅 2026-04-15
CVSS 2.7 Dossier →
Component: mattermost

Mattermost Plugins versions <=2.1.3.0 fail to limit the request body size on the {{/changes}} webhook endpoint which allows an authenticated attacker ...

📅 2026-04-09
CVSS 3.7 Dossier →
Component: mattermost_server

Mattermost Plugins versions <=2.3.1 fail to limit the request body size on the {{/lifecycle}} webhook endpoint which allows an authenticated attacker ...

📅 2026-04-09
CVSS 3.7 Dossier →
Component: focalboard

** UNSUPPORTED WHEN ASSIGNED ** Focalboard version 8.0 fails to validate file ownership when serving uploaded files. This allows an authenticated atta...

📅 2026-04-03
CVSS 4.3 Dossier →
Component: focalboard

** UNSUPPORTED WHEN ASSIGNED ** Focalboard version 8.0 fails to sanitize category IDs before incorporating them into dynamic SQL statements when reord...

📅 2026-04-03
CVSS 8.1 Dossier →
CVE-2026-3116 MEDIUM
Component: mattermost_server

Mattermost Plugins versions <=11.4 11.0.4 11.1.3 11.3.2 10.11.11.0 fail to validate incoming request size which allows an authenticated attacker to ca...

📅 2026-03-26
CVSS 4.9 Dossier →
CVE-2026-3115 MEDIUM
Component: mattermost_server

Mattermost versions 11.2.x <= 11.2.2, 10.11.x <= 10.11.10, 11.4.x <= 11.4.0, 11.3.x <= 11.3.1 fail to apply view restrictions when retrieving group me...

📅 2026-03-26
CVSS 4.3 Dossier →
CVE-2026-3114 MEDIUM
Component: mattermost_server

Mattermost versions 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, 10.11.x <= 10.11.11 fail to validate decompressed archive entry sizes during...

📅 2026-03-26
CVSS 6.5 Dossier →
Page 3 of 26 (602 Total Records)