CVE-2026-4054mediumCWE-754

CVE-2026-4054: fallo de gravedad media en Mattermost

SVG content served through Mattermost image proxy despite Content-Type restrictions causes client-side 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 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 the response body of proxied images, which allows a remote attacker to enact client-side DoS via an SVG file served from an attacker-controlled origin under a non-SVG Content-Type header (e.g. image/png) embedded in an og:image meta tag or Markdown image link.. Mattermost Advisory ID: MMSA-2026-00630
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
Productos afectados
Mattermost · Mattermost
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