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CVE-2026-6517

Estado: AnalizadaAlta (7.7)—

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

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

Acceso autenticado en red (PR:L) que permite interceptar credenciales NTLM mediante imagen embebida que redirige a servidor externo; sin restricción en dominios permitidos (CWE-522: almacenamiento de credenciales inseguro).

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Privileged Account ManagementNetwork SegmentationLimit Access to Resource Over NetworkDisable or Remove Feature or ProgramVulnerability ScanningUser Training

Tecnologías afectadas (1)

Mattermost — Mattermost Desktop

CWE

Referencias

JSON original (NVD)

Mostrar
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