CVE-2026-28759mediumCWE-863

CVE-2026-28759: fallo de gravedad media en Mattermost

Insufficient authorization in shared channel membership sync allows remote cluster to remove users from arbitrary channels

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 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to validate that a remote cluster has access to a channel before processing membership removal requests during shared channel membership sync, which allows a malicious remote cluster to remove any user from any channel, including private channels, via crafted membership sync messages targeting channels the remote cluster is not authorized to access. Mattermost Advisory ID: MMSA-2026-00576
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Productos afectados
Mattermost · Mattermost
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