CVE-2026-9793
Full vulnerability record from the local CVENow database.
Description
A flaw was found in Keycloak. When a JSON Web Encryption (JWE) encrypted request object is submitted, Keycloak may incorrectly process unsigned claims if the decrypted content is raw JSON, bypassing the configured signature policy. This allows a remote attacker to submit unauthorized claims, leading to a compromise of data integrity within the OpenID Connect (OIDC) authorization flow. While a redirect URI allowlist acts as a compensating control, this vulnerability violates OIDC Core and Financial-grade API (FAPI) signing requirements.
Severity
HIGH
CVSS score
7.5
(v3.1)
Vulnerability status
Modified
Source identifier
Published
2026-05-28 05:16:40.697000
Last modified
2026-10-26 12:10:00.130000
View original CVE JSON
{
"id": "CVE-2026-9793",
"sourceIdentifier": "[email protected]",
"published": "2026-05-28T05:16:40.697",
"lastModified": "2026-10-26T12:10:00.130",
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"value": "A flaw was found in Keycloak. When a JSON Web Encryption (JWE) encrypted request object is submitted, Keycloak may incorrectly process unsigned claims if the decrypted content is raw JSON, bypassing the configured signature policy. This allows a remote attacker to submit unauthorized claims, leading to a compromise of data integrity within the OpenID Connect (OIDC) authorization flow. While a redirect URI allowlist acts as a compensating control, this vulnerability violates OIDC Core and Financial-grade API (FAPI) signing requirements."
},
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"value": "Se encontró un fallo en Keycloak. Cuando se envía un objeto de solicitud cifrado con JSON Web Encryption (JWE), Keycloak puede procesar incorrectamente las reclamaciones sin firmar si el contenido descifrado es JSON en bruto, eludiendo la política de firma configurada. Esto permite a un atacante remoto enviar reclamaciones no autorizadas, lo que lleva a un compromiso de la integridad de los datos dentro del flujo de autorización de OpenID Connect (OIDC). Si bien una lista de permitidos de URI de redirección actúa como un control compensatorio, esta vulnerabilidad viola los requisitos de firma de OIDC Core y Financial-grade API (FAPI)."
}
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