CVE-2026-18211

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.

CVSS v3 4.2 MEDIUM

4.2^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-18211	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2508306	Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:redhat:build_of_keycloak:-:*:*:*:-:*:*:*

History

No history.

Information

Published : 2026-07-31 08:16

Updated : 2026-08-07 14:30

NVD link : CVE-2026-18211

Mitre link : CVE-2026-18211

CVE.ORG link : CVE-2026-18211

JSON object : View

Products Affected

redhat

build_of_keycloak

CWE

CWE-20

Improper Input Validation

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