Vulnerability Description
A flaw was found in Keycloak. A missing authorization check in the GroupResource.addChild() endpoint within the Admin REST API allows an authenticated user with limited administrative privileges to reparent any existing group. When Fine-Grained Admin Permissions v2 (FGAPv2) is enabled, an attacker with management rights over a single low-privilege group can reparent a highly privileged group (such as one possessing the realm-admin role) under their managed group. Because group permissions follow a hierarchical structure, this action unauthorizedly grants the attacker management and password-reset capabilities over the members of the targeted privileged group. An attacker can exploit this to reset an administrator's password, compromise the account, and achieve a full realm takeover, leading to a complete compromise of confidentiality, integrity, and availability.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Redhat | Build Of Keycloak | >= 26.4, < 26.4.13 |
Related Weaknesses (CWE)
References
- https://access.redhat.com/errata/RHSA-2026:30049Third Party Advisory
- https://access.redhat.com/errata/RHSA-2026:30050Third Party Advisory
- https://access.redhat.com/errata/RHSA-2026:30083Third Party Advisory
- https://access.redhat.com/errata/RHSA-2026:30084Third Party Advisory
- https://access.redhat.com/security/cve/CVE-2026-9099Third Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2480182Third Party Advisory
- https://access.redhat.com/errata/RHSA-2026:30049Third Party Advisory
- https://access.redhat.com/errata/RHSA-2026:30050Third Party Advisory
- https://access.redhat.com/errata/RHSA-2026:30083Third Party Advisory
- https://access.redhat.com/errata/RHSA-2026:30084Third Party Advisory
- https://access.redhat.com/security/cve/CVE-2026-9099Third Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2480182Third Party Advisory
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-9099.jsonThird Party Advisory
FAQ
What is CVE-2026-9099?
CVE-2026-9099 is a vulnerability with a CVSS score of 7.7 (HIGH). A flaw was found in Keycloak. A missing authorization check in the GroupResource.addChild() endpoint within the Admin REST API allows an authenticated user with limited administrative privileges to re...
How severe is CVE-2026-9099?
CVE-2026-9099 has been rated HIGH with a CVSS base score of 7.7/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-9099?
Check the references section above for vendor advisories and patch information. Affected products include: Redhat Build Of Keycloak.