CVE-2026-9803
Full vulnerability record from the local CVENow database.
Description
A flaw was found in Keycloak's ClientRegistrationAuth component. A remote unauthenticated attacker can exploit this vulnerability by sending a specially crafted POST request with a malformed 'Authorization: Bearer' header to any client registration endpoint. This can lead to an ArrayIndexOutOfBoundsException, causing the server to return an HTTP 500 error and resulting in a Denial of Service (DoS) for the affected service.
Severity
MEDIUM
CVSS score
5.3
(v3.1)
Vulnerability status
Modified
Source identifier
Published
2026-05-28 06:16:29.750000
Last modified
2026-10-26 12:10:00.130000
View original CVE JSON
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"sourceIdentifier": "[email protected]",
"published": "2026-05-28T06:16:29.750",
"lastModified": "2026-10-26T12:10:00.130",
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},
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"value": "Se encontró un fallo en el componente ClientRegistrationAuth de Keycloak. Un atacante remoto no autenticado puede explotar esta vulnerabilidad enviando una solicitud POST especialmente diseñada con una cabecera ’Authorization: Bearer’ malformada a cualquier endpoint de registro de cliente. Esto puede llevar a una ArrayIndexOutOfBoundsException, haciendo que el servidor devuelva un error HTTP 500 y resultando en una Denegación de Servicio (DoS) para el servicio afectado."
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"attackComplexity": "LOW",
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"source": "[email protected]"
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