CVE-2026-18211
No fix known EPSS <1%CVSS 4.2
A flaw was found in the secure-client-uris client policy executor within Keycloak core services. This component is responsible for enforcing security requirements on client configurations, such as requiring encrypted connections for redirect URIs. Due to an improper check that only looks at the start of a web address rather than properly verifying the host, an attacker can bypass these security restrictions by using a specially crafted domain name. This could allow an attacker to intercept sensitive authentication codes over unencrypted connections.
Products: Red Hat Build of Keycloak, Red Hat Data Grid 8, Red Hat JBoss Enterprise Application Platform Expansion Pack, Red Hat Single Sign-On 7