Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21, 11.8.x <= 11.8.3 fails to validate WebSocket command field types which allows an authenticated user to crash the plugin process and deny service to all Boards users via a custom_focalboard_SUBSCRIBE_TEAM message with a non-string teamId.. Mattermost Advisory ID: MMSA-2026-00687
Metrics
Affected Vendors & Products
Advisories
No advisories yet.
Fixes
Solution
Update Mattermost to versions 11.9.0, 11.7.7, 10.11.22, 11.8.4 or higher.
Workaround
No workaround given by the vendor.
References
| Link | Providers |
|---|---|
| https://mattermost.com/security-updates |
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History
Mon, 17 Aug 2026 23:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Mattermost
Mattermost mattermost |
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| Vendors & Products |
Mattermost
Mattermost mattermost |
Mon, 17 Aug 2026 22:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21, 11.8.x <= 11.8.3 fails to validate WebSocket command field types which allows an authenticated user to crash the plugin process and deny service to all Boards users via a custom_focalboard_SUBSCRIBE_TEAM message with a non-string teamId.. Mattermost Advisory ID: MMSA-2026-00687 | |
| Title | Boards plugin panics on WebSocket command with non-string field types | |
| Weaknesses | CWE-704 | |
| References |
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| Metrics |
cvssV3_1
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Projects
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Status: PUBLISHED
Assigner: Mattermost
Published:
Updated: 2026-08-17T22:04:30.830Z
Reserved: 2026-05-29T10:40:50.902Z
Link: CVE-2026-10080
No data.
Status : Received
Published: 2026-08-17T22:16:58.607
Modified: 2026-08-17T22:16:58.607
Link: CVE-2026-10080
No data.
OpenCVE Enrichment
Updated: 2026-08-17T23:30:04Z
Weaknesses