CVE-2025-12689

published 2025-12-17

CVE-2025-12689: 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…

Priority P3 36 medium 6.5 CVSS 3.1

AV N AC L PR L UI N S U C N I N A H

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

7 ranges

Vendor	Product	Version range	Fixed in
github.com	mattermost_mattermost-plugin-calls	>= 0 < 1.11.0	1.11.0
mattermost	mattermost	10.11.0 – 10.11.6	—
mattermost	mattermost	10.12.0 – 10.12.2	—
mattermost	mattermost	11.0.0 – 11.0.4	—
mattermost	mattermost_server	>= 10.11.0 < 10.11.7	10.11.7
mattermost	mattermost_server	>= 10.12.0 < 10.12.3	10.12.3
mattermost	mattermost_server	>= 11.0.0 < 11.0.5	11.0.5

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CWE-1287