Auth bypass in Red Hat Build Of Keycloak

CVE-2026-18570

A flaw was found in the full-scope-disabled client-policy executor within the keycloak-services component. This component is responsible for enforcing security policies during client registration and configuration in Red Hat Build of Keycloak. The issue occurs because the executor only validates the fullScopeAllowed field when it is explicitly provided in a request. By omitting this field, a delegated user can bypass the policy, resulting in a client created with full scope access. This allows the client to obtain tokens with unauthorized role mappings.

Vulnerability class: Broken Access Control

EPSS: 0.001 (3.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-18570?
CVE-2026-18570 is a medium-severity vulnerability in Red Hat Build Of Keycloak, classified under Missing Authorization. CVSS score: 5.4/10. Published 2026-08-02.
How severe is CVE-2026-18570?
Medium severity. CVSS v3 base score is 5.4 out of 10.