CVE-2026-18573: medium-severity vulnerability in Red Hat build of Keycloak 26.6
Keycloak-services: keycloak-services: client access-type policy condition bypass during client update
Published · Updated
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.5epss 0.5%
A flaw was found in the keycloak-services component of Keycloak, which is used for managing authentication and authorization flows. The issue occurs when a realm administrator configures client policies to enforce specific authentication requirements on confidential clients. Due to improper evaluation of the client state during an update operation, an attacker with client management permissions can bypass these security policies by first creating a public client and then updating it to a confidential client with weaker authentication. This can result in the persistence of clients that do not comply with the intended security hardening of the realm.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
Affected products
Red Hat · Red Hat build of Keycloak 26.6Red Hat · Red Hat build of Keycloak 26.6.7Red Hat · Red Hat Data Grid 8Red Hat · Red Hat JBoss Enterprise Application Platform Expansion PackRed Hat · Red Hat Single Sign-On 7Related CVEs — Red Hat build of Keycloak 26.6
In the same product, most dangerous first.
CVE-2026-18963CRITICALKeycloak-services: keycloak-services: unauthenticated account takeover via reset-credentials flow bypassEPSS 4.7%CVE-2024-1635HIGHUndertow: out-of-memory error after several closed connections with wildfly-http-client protocolEPSS 4.6%CVE-2023-5685HIGHXnio: stackoverflowexception when the chain of notifier states becomes problematically bigEPSS 3.5%CVE-2024-5971HIGHUndertow: response write hangs in case of java 17 tlsv1.3 newsessionticketEPSS 2.9%CVE-2023-3223HIGHUndertow: outofmemoryerror due to @multipartconfig handlingEPSS 2.7%CVE-2024-7885HIGHUndertow: improper state management in proxy protocol parsing causes information leakageEPSS 2.6%