PT-2026-66726 · Red Hat · Red Hat Build Of Keycloak+3

CVE-2026-18211 · Published 2026-07-31 · Updated 2026-07-31

Mitre

CVSS v3.1

4.2

Medium

Base vector

AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N

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.

Fix

RCE

Weakness Enumeration

CWE-20

Related Identifiers

CVE-2026-18211

Affected 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

References · 3

• https://nvd.nist.gov/vuln/detail/CVE-2026-18211 · Security Note
• https://access.redhat.com/security/cve/CVE-2026-18211 · Note
• https://bugzilla.redhat.com/show_bug.cgi?id=2508306 · Note