cvedb.io
CVE-2026-9803
MEDIUM · CVSS 5.3
EPSS exploitation probability: 0%
Published 2026-05-28T06:16:29.750 · Last modified 2026-06-26T08:16:35.157

Summary

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.

Affected products

redhat — build_of_keycloak

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.