Description
A flaw was found in the backchannel logout endpoint of the keycloak-services component, which is part of the Red Hat Build of Keycloak. This component handles authentication and session management for applications. The issue occurs when an OIDC identity provider is configured to skip signature validation. In this specific setup, the system incorrectly accepts logout requests that have no cryptographic signature. An attacker who knows certain technical details about a user's session can use this flaw to force that user to be logged out, potentially disrupting their work.
Affected products
redhat: build of keycloak
References4
- access.redhat.com/security/cve/CVE-2026-18569 Vendor Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2509755 Issue TrackingVendor Advisory
- access.redhat.com/errata/RHSA-2026:95761
- access.redhat.com/errata/RHSA-2026:95762
Metrics
- CVSS 3.1
-
3.7
LOW
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L - EPSS — exploit probability
- 0% percentile: 25 · as of 13 November 2026
- CWE
- CWE-347
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