CVE-2026-19541: fallo de gravedad media en Mattermost
Outgoing OAuth connection client secret exposure during connection validation
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 6.5epss 0.2%
Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 fail to require re-entry of the stored client secret when validating an outgoing OAuth connection, which allows an authenticated user with permission to manage outgoing OAuth connections to obtain the secret via pointing the token URL at an attacker-controlled endpoint and triggering validation.. Mattermost Advisory ID: MMSA-2026-00761
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Productos afectados
Mattermost · MattermostCVEs relacionadas — Mattermost
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Referencias
https://mattermost.com/security-updates