CVE-2026-18215

Keycloak provides a way to let users log in using Microsoft accounts while restricting access to a specific organization (tenant). A flaw was discovered where this restriction is ignored when using the token exchange feature. This means an attacker with a valid Microsoft token from a completely different organization could gain access to the Keycloak realm, potentially accessing sensitive data or performing unauthorized actions.

CVSS v3 6.8 MEDIUM

6.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:68277
https://access.redhat.com/errata/RHSA-2026:68278
https://access.redhat.com/security/cve/CVE-2026-18215	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2508309	Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

16 Sep 2026, 16:17

Type	Values Removed	Values Added
References		() https://access.redhat.com/errata/RHSA-2026:68277 - () https://access.redhat.com/errata/RHSA-2026:68278 -

Information

Published : 2026-07-31 08:16

Updated : 2026-09-16 19:17

NVD link : CVE-2026-18215

Mitre link : CVE-2026-18215

CVE.ORG link : CVE-2026-18215

JSON object : View

Products Affected

redhat

build_of_keycloak

CWE

CWE-287

Improper Authentication

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