CVE-2026-18569

LOW
INFO Priority: 0.01 BB Relevance: 57/100
Published: 2026-08-04 Modified: 2026-11-07 First seen: 2026-11-07 Status: active

Attack Surface

Network No Auth No Interaction

CVSS Vector Breakdown

AV: Network
AC: High
PR: None
UI: None
S: Unchanged
C: None
I: None
A: Low

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 Software (1)

VendorProductVersion
redhat build_of_keycloak -

References & Advisories (4)

https://access.redhat.com/errata/RHSA-2026:95761
vendor-advisory x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:95762
vendor-advisory x_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2509755
issue-tracking x_refsource_REDHAT

Bug Bounty Relevance

57 / 100
✓ Network accessible
✓ No authentication
✓ No user interaction

CVSS Score

3.7 / 10.0 v3.1
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L

EPSS — Exploitation Probability

0.31%
Raw Score 0.003140
Percentile 24.6%
Date 2026-11-13

EPSS Trend

2026-11-13
0.00314
2026-11-12
0.00314
2026-11-10
0.00314
2026-11-09
0.00314
2026-11-08
0.00314
2026-11-07
0.00250
2026-11-06
0.00250

Intelligence Sources

mitre ref →
nvd ref →