Description (CNA)
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 (CNA)
| Vendor / product | Versions |
|---|---|
| Red Hat / Red Hat build of Keycloak 26.4 | unaffected 26.4.13-1 before * |
| Red Hat / Red Hat build of Keycloak 26.4 | unaffected 26.4-19 before * |
| Red Hat / Red Hat build of Keycloak 26.4 | unaffected 26.4-19 before * |
| Red Hat / Red Hat build of Keycloak 26.4.13 | unaffected |
| Red Hat / Red Hat build of Keycloak 26.6 | unaffected 26.6.3-3 before * |
| Red Hat / Red Hat build of Keycloak 26.6 | unaffected 26.6-6 before * |
| Red Hat / Red Hat build of Keycloak 26.6 | unaffected 26.6-6 before * |
| Red Hat / Red Hat build of Keycloak 26.6.3 | unaffected |
CWE
CWE-125
References
- https://access.redhat.com/errata/RHSA-2026:25097
- https://access.redhat.com/errata/RHSA-2026:25098
- https://access.redhat.com/errata/RHSA-2026:30049
- https://access.redhat.com/errata/RHSA-2026:30050
- https://access.redhat.com/security/cve/CVE-2026-9803
- https://bugzilla.redhat.com/show_bug.cgi?id=2482465
ADP enrichment
No English description supplied.
No references supplied.