CVE-2025-12390

mediumpriority · track · 0EPSS 0.001 · 3 %ileDEEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.14% (3rd) EPSS

CVSS 6 · medium

Is it mine?

8 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · cert_bund · osv

EPSS · scored 2026-10-24

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.

cvss

Technical severity, 0–10. One row per scoring source.

6.0

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.16mediumCVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:Nsecondary · ENISA EU

v3.16mediumCVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:Nsecondary · secalert@redhat.com USexploitability 0.8 · impact 5.2

v3.16mediumCVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:Nsecondary · OSV

v3.15.5mediumCVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-384USCWE-384US

affected products (8)

Products and version ranges known to be affected.

Open Source Keycloakall versionscert_bundDEcpe:/a:keycloak:keycloak:-
Red Hat Enterprise Linux Keycloakall versionscert_bundDEcpe:/o:redhat:enterprise_linux:keycloak
KeyCloak0 → 26.0.0enisa_euvdEU
Red Hat build of Keycloak 26.2< 26.2-12enisa_euvdEU
Red Hat build of Keycloak 26.2< 26.2.11-1enisa_euvdEU
Red Hat build of Keycloak 26.4< 26.4-3enisa_euvdEU
Red Hat build of Keycloak 26.4< 26.4.4-1enisa_euvdEU
Maven org.keycloak:keycloak-services< 26.0.0osvUSpkg:maven/org.keycloak/keycloak-services

advisories (2)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2025-2438Keycloak: Schwachstelle ermöglicht Umgehen von SicherheitsvorkehrungenDeutsch2025-10-28csaf · cert_bundDE
Ein lokaler Angreifer kann eine Schwachstelle in Keycloak ausnutzen, um Sicherheitsvorkehrungen zu umgehen.
GHSA-rg35-5v25-mqvpKeycloak vulnerable to session takeovers due to reuse of session identifiers2025-10-28ghsa · osvUS
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.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cert_bund osv NVD CVE.org MITRE

published 2025-10-28modified 2026-10-18

references (17)

External citations — patches, advisories, analysis.

scry

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