CVE-2026-9086highCWE-79

CVE-2026-9086: fallo de gravedad alta en Red Hat build of Keycloak 26.4

Keycloak: keycloak: cross-site scripting (xss) via case-insensitive uri validation bypass

Publicada el · Actualizada el

Seguir esta CVE+ Monitorear Red Hat build of Keycloak+ Monitorear org.keycloak:keycloak-services

Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.

41Vexday Risk Score

Sin señal de explotación. Ella tiene prueba de concepto pública.

ssvc Attendcvss 7.3epss 0.8%
de la publicación al arma46 días
Publicada en NVD25 jun
1ª PoC+46d
A flaw was found in Keycloak. A remote attacker with administrative privileges, specifically those with `manage-client` permission or access to client registration endpoints, could bypass client Uniform Resource Identifier (URI) validation. This is achieved by registering a malicious client with a specially crafted redirect URI using a case-insensitive `javascript:` or `data:` scheme. This Cross-Site Scripting (XSS) vulnerability allows for arbitrary code execution in the Keycloak origin when a victim clicks the crafted link, such as in the logout flow or the Admin Console.
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N
Productos afectados
Red Hat · Red Hat build of Keycloak 26.4Red Hat · Red Hat build of Keycloak 26.4.13Red Hat · Red Hat build of Keycloak 26.6Red Hat · Red Hat build of Keycloak 26.6.4
PoCs públicas encontradas — 1
githubgithub.com/Saku0512/CVE-2026-9086-poc★ 1
⚠ Recursos públicos, para evaluar la exposición de sistemas que controlas o estás autorizado a probar. Prueba solo con autorización.
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