CVE-2026-9086

A flaw was found in Keycloak. A remote attacker with administrative privileges, specifically those with `manage-client` permission or access to client registration endpoints, could bypass client Uniform Resource Identifier (URI) validation. This is achieved by registering a malicious client with a specially crafted redirect URI using a case-insensitive `javascript:` or `data:` scheme. This Cross-Site Scripting (XSS) vulnerability allows for arbitrary code execution in the Keycloak origin when a victim clicks the crafted link, such as in the logout flow or the Admin Console.

CVSS v3 7.3 HIGH

7.3^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.1 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:30049	Third Party Advisory
https://access.redhat.com/errata/RHSA-2026:30050	Third Party Advisory
https://access.redhat.com/errata/RHSA-2026:30083	Third Party Advisory
https://access.redhat.com/errata/RHSA-2026:30084	Third Party Advisory
https://access.redhat.com/security/cve/CVE-2026-9086	Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2480170	Third Party Advisory
https://access.redhat.com/errata/RHSA-2026:30049	Third Party Advisory
https://access.redhat.com/errata/RHSA-2026:30050	Third Party Advisory
https://access.redhat.com/errata/RHSA-2026:30083	Third Party Advisory
https://access.redhat.com/errata/RHSA-2026:30084	Third Party Advisory
https://access.redhat.com/security/cve/CVE-2026-9086	Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2480170	Third Party Advisory
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-9086.json	Third Party Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:redhat:build_of_keycloak::::::::
	cpe:2.3:a:redhat:build_of_keycloak::::::::

History

No history.

Information

Published : 2026-06-25 17:17

Updated : 2026-07-15 01:17

NVD link : CVE-2026-9086

Mitre link : CVE-2026-9086

CVE.ORG link : CVE-2026-9086

JSON object : View

Products Affected

redhat

build_of_keycloak

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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