CVE-2025-12689Medium· 6.5▾ SunlitMattermost 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.
▾ Sunlit zone — Low / medium · no exploitation signal
impact 35.8 · likelihood 0.1 · exploitation 0
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Exploit-prediction probability, daily snapshots since Oct 13.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
Last analysed / modified upstream
0.3%
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.
mattermost_server >= 10.11.0, < 10.11.7mattermost_server >= 10.12.0, < 10.12.3mattermost_server >= 11.0.0, < 11.0.5Upgrade past the affected range:
mattermost_server 11.0.5Connected by shared product, vendor, weakness, or advisory.
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