Junglewise Threat Intelligence

CVE-2026-18573: Keycloak client policy bypass in confidential client creation

CVE-2026-18573 · Severity: medium · CVSS 6.5 · Published 2026-08-02

Executive brief

Keycloak is an open-source authentication and authorization platform used to manage user login and access control. A security flaw allows realm administrators' clients with management permissions to bypass enforced security policies by creating a public client and then converting it to a confidential client with weaker authentication requirements, resulting in non-compliant security configurations persisting in the system.

Technical details

The vulnerability is a policy enforcement bypass in the keycloak-services component affecting client policy evaluation during client state updates. An attacker with client management permissions can circumvent realm administrator-configured client policies by exploiting improper validation during the transition from public to confidential client mode. The attack requires authenticated access (client management role) and proceeds by creating a public client and then updating it to confidential status with relaxed authentication settings. This allows persistence of clients that violate the realm's intended security hardening policies. A fix is expected to improve state validation during client updates.

Affected products

  • Keycloak Keycloak

Timeline

  • 2026-08-02: disclosed

References

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