CVE-2026-18569
Keycloak-services: keycloak-services: oidc backchannel logout accepts unsigned forged logout tokens
LOW 3.7
At a glance
- Source
- NVD
- EPSS
- EPSS 0.25 % · percentile 16 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- redhat
- NVD status
- Analyzed
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.
Weaknesses (CWE)
- CWE-347 — Improper Verification of Cryptographic Signature
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | LOW 3.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L | redhat |
| CVSS 3.1 | LOW 3.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L | NVD · secalert@redhat.com (Secondary) |
European references
- ENISA EUVD · EUVD-2026-52575
- GCVE · GCVE-0-2026-18569
Affected configurations (NVD CPE)
cpe:2.3:a:redhat:build_of_keycloak:-:*:*:*:-:*:*:*
Affected products
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |