GHSA-cpf7-j4cf-vqx4
Keycloak has an Out-of-bounds Read
At a glance
- Published
- Updated
- CVE
- CVE-2026-9803
- CVSS_V3
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
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.
Affected packages
| Package | Versions |
|---|---|
| Maven · org.keycloak:keycloak-services | introduced 0, last affected 26.4.7 |
| Maven · org.keycloak:keycloak-services | introduced 26.5.0, fixed 26.6.3 |
References
- https://nvd.nist.gov/vuln/detail/CVE-2026-9803 ADVISORY
- https://github.com/keycloak/keycloak/issues/49433 WEB
- https://github.com/keycloak/keycloak/pull/49500 WEB
- https://github.com/keycloak/keycloak/pull/49617 WEB
- https://github.com/keycloak/keycloak/pull/49618 WEB
- https://github.com/keycloak/keycloak/commit/2b8692499e907e6205be0bd9c8a4da5d46f6ca30 WEB
- https://github.com/keycloak/keycloak/commit/3fc06909cc93eb5c4739a712fa350de625812e04 WEB
- https://github.com/keycloak/keycloak/commit/ef06df91d344c7e99fcb82987ef6adb854f30789 WEB
- https://access.redhat.com/errata/RHSA-2026:25097 WEB
- https://access.redhat.com/errata/RHSA-2026:25098 WEB
- https://access.redhat.com/errata/RHSA-2026:30049 WEB
- https://access.redhat.com/errata/RHSA-2026:30050 WEB
- https://access.redhat.com/security/cve/CVE-2026-9803 WEB
- https://bugzilla.redhat.com/show_bug.cgi?id=2482465 WEB
- https://github.com/keycloak/keycloak PACKAGE
Sources
| Source | Licence |
|---|---|
| OSV.dev | CC-BY 4.0 — GitHub Advisory Database |