CVE-2026-87995
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.8.11 until 0.11.1, src/lib/components/chat/FileNav/PortPreview.svelte rendered terminal port content in an iframe sandbox containing both allow-scripts and allow-same-origin. Because the terminal proxy serves that content from the Open WebUI origin, an authenticated user with access to a shared terminal server could host script on a previewed port and take over a victim's account when the victim opened the preview. This issue is fixed in version 0.11.1.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N
- Puntuación base: 8.7
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.42%
- Percentil entre todas las CVEs puntuadas: 34
- Fecha de la puntuación: 5/10/2026
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.
- Explotación
T1189Drive-by Compromiseinitial access90 % - Impacto principal
T1078Valid Accountsstealth · persistence · privilege escalation · initial access85 % - Impacto secundario
T1059.007JavaScriptexecution75 %
XSS almacenado en iframe sandbox con allow-scripts y allow-same-origin permite inyectar scripts que roban sesión autenticada (CWE-79). Requiere interacción (UI:R) pero la explotación es T1189 (drive-by en preview). El atacante logra acceso a la cuenta de la víctima.
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
Tecnologías afectadas (1)
CWE
- CWE-79, CWE-1021
Referencias
- https://github.com/open-webui/open-webui/commit/54d7a223707f03172efbb9e754db6e69709956d0
- https://github.com/open-webui/open-webui/releases/tag/v0.11.1
- https://github.com/open-webui/open-webui/security/advisories/GHSA-jmc6-2wr8-h3wj
- https://github.com/open-webui/open-webui/security/advisories/GHSA-jmc6-2wr8-h3wj
JSON original (NVD)
Mostrar
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