CVE-2026-5163mediumCWE-862

CVE-2026-5163: fallo de gravedad media en Mattermost

Missing authorization check in AI message rewrite endpoint allows access to private thread content

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 11.5.x <= 11.5.1 fail to verify channel membership when processing AI-assisted message rewrites which allows an authenticated attacker to read the content of threads in private channels and direct messages they do not have access to via a crafted request to the post rewrite endpoint.. Mattermost Advisory ID: MMSA-2026-00645
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Productos afectados
Mattermost · Mattermost
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