CVE-2026-21386mediumCWE-203

CVE-2026-21386: fallo de gravedad media en Mattermost

Private channel enumeration via /mute slash command

Publicada el

Seguir esta CVE+ Monitorear Mattermost+ Monitorear github.com/mattermost/mattermost-server

Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.

13Vexday Risk Score

Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.

ssvc Trackcvss 4.3epss 0.2%
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to use consistent error responses when handling the /mute command which allows an authenticated team member to enumerate private channels they are not authorized to know about via differing error messages for nonexistent versus private channels. Mattermost Advisory ID: MMSA-2026-00588
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Productos afectados
Mattermost · Mattermost
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