CVE-2025-12390

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

MEDIUM
6
CVSS Score
Published: October 28, 2025 at 01:23 PM UTC
Updated: October 18, 2026 at 09:10 PM UTC
1 product affected across 1 vendorKeycloak

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Severity
MEDIUM6
Exploit prediction
EPSS 0.1%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

0 ≤ v < 26.0.00
Affected range stops below 26.0.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (7)

VDB Entryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/security/cve/CVE-2025-12390
Issue Trackingx_refsource_REDHAT
Source: cverecord
https://bugzilla.redhat.com/show_bug.cgi?id=2406793
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2025:21370
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2025:21371
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2025:22088
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2025:22089

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

6MEDIUMredhat
Attack Vector
LOCAL
Complexity
HIGH
Privileges
LOW
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-384

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