CVE-2025-12689
Medium · 6.5Mattermost fails to check Websocket request for proper UTF-8 format potentially crashing Calls plug-in
CVSS
6.5
EPSS
0.3%
Published
Dec 17, 2025
CISA due date
—
The record
Mattermost versions 11.0.x <= 11.0.4, 10.12.x <= 10.12.2, 10.11.x <= 10.11.6 fail to check WebSocket request field for proper UTF-8 format, which allows attacker to crash Calls plug-in via sending malformed request.
Affected packages
| Ecosystem | Package | Introduced | Fixed |
|---|---|---|---|
| Go | github.com/mattermost/mattermost-plugin-calls | 0 | 1.11.0 |
| openSUSE:Leap 15.6 | govulncheck-vulndb | 0 | 0.0.20251230T014957-150000.1.134.1 |
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