CVE-2026-4635mediumCWE-362

CVE-2026-4635: fallo de gravedad media en Mattermost

Persistent notification timing attack causing server denial of service

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 6.5epss 0.2%
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to archive the channel before removing persistent notifications which allows authenticated user to crash the server via timing the creation of persistent notification message between the server deleting existing persistent notifications and archiving the channel.. Mattermost Advisory ID: MMSA-2026-00637
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Productos afectados
Mattermost · Mattermost
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