CVE-2025-12390

Org.keycloak.protocol.oidc.endpoints.logoutendpoint: offline session takeover due to reused authentication session id

State: Published
Severity: 6.0 Medium
Published: Oct 28, 2025
Updated: Jul 30, 2026
Reserved: Oct 28, 2025

Description

A flaw was found in Keycloak. In Keycloak where a user can accidentally get access to another user's session if both use the same device and browser. This happens because Keycloak sometimes reuses session identifiers and doesn’t clean up properly during logout when browser cookies are missing. As a result, one user may receive tokens that belong to another user.

Scores

CVSS	Score	Vector	Source
3.1	6.0 Medium	CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N	redhat

Weaknesses

CWE-384 Session Fixation

Affected Products

Product	Versions
keycloakKeycloak	before 26.0.0Affected
Red Hat build of Keycloak 26.2Red Hat	26.2.11-1 and laterNot affected
Red Hat build of Keycloak 26.2Red Hat	26.2-12 and laterNot affected
Red Hat build of Keycloak 26.2Red Hat	26.2-12 and laterNot affected
Red Hat build of Keycloak 26.2.11Red Hat
Red Hat build of Keycloak 26.4Red Hat	26.4.4-1 and laterNot affected
Red Hat build of Keycloak 26.4Red Hat	26.4-3 and laterNot affected
Red Hat build of Keycloak 26.4Red Hat	26.4-3 and laterNot affected
Red Hat build of Keycloak 26.4.4Red Hat

References

RHSA-2025:21370vendor-advisory
RHSA-2025:21371vendor-advisory
RHSA-2025:22088vendor-advisory
RHSA-2025:22089vendor-advisory
https://access.redhat.com/security/cve/CVE-2025-12390vdb-entry
RHBZ#2406793issue-tracking
https://github.com/keycloak/keycloak/issues/43853

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