CVE-2026-6517: fallo de gravedad media en Mattermost
Mattermost Desktop App fails to restrict the allow list of domains which NTLM credentials are passed
Publicada el
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 6.3epss 0.2%
Mattermost Desktop App versions <=6.1 5.5.13.0 fail to restrict the allow list of domains to which NTLM credentials were forwarded to in the Mattermost Desktop App which allows any user on a server without the image proxy enabled to intercept other users credentials via embedding an image that routes to an external web server. Mattermost Advisory ID: MMSA-2026-00651
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N
Productos afectados
Mattermost · MattermostCVEs relacionadas — Mattermost
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Referencias
https://mattermost.com/security-updates