CVE-2026-9087

highpriority · track · 32EPSS 0.003 · 24 %ileDEEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.31% (24th) EPSS

CVSS 8.1 · high

Is it mine?

10 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · cert_bund · nvd

EPSS · scored 2026-10-27

A flaw was found in Keycloak. The cross-session verification proof is keyed only by (local userId, idpAlias) and is not bound to the upstream identity that was actually verified, so a second upstream account on the same IdP can consume it and get linked to the victim's local account.

cvss

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

8.1

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.4–8.1

v3.18.1highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 5.2

v3.16.4mediumCVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:Nsecondary · ENISA EU

v3.16.4mediumCVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:Nsecondary · secalert@redhat.com USexploitability 1.2 · impact 5.2

v3.16.4mediumCVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:Nsecondary · OSV

v3.17.4highCVSS:3.1/AV:N/AC:L/PR:N/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-639USCWE-639US

affected products (10)

Products and version ranges known to be affected.

Open Source Keycloakall versionscert_bundDEcpe:/a:keycloak:keycloak:-
Open Source Keycloak <26.6.3all versionscert_bundDE
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
Open Source Keycloak< 26.6.3cert_bundDE
Red Hat Red Hat build of Keycloak 26.4< 26.4-19enisa_euvdEU
Red Hat Red Hat build of Keycloak 26.4< 26.4.13-1enisa_euvdEU
Red Hat Red Hat build of Keycloak 26.6< 26.6-6enisa_euvdEU
Red Hat Red Hat build of Keycloak 26.6< 26.6.3-3enisa_euvdEU
redhat build of keycloakall versionsnvdUScpe:2.3:a:redhat:build_of_keycloak:*:*:*:*:*:*:*:*
Maven org.keycloak:keycloak-services< 26.6.3osvUSpkg:maven/org.keycloak/keycloak-services

advisories (2)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2026-1616Keycloak: Schwachstelle ermöglicht Umgehen von SicherheitsvorkehrungenDeutsch2026-05-20csaf · cert_bundDE
Ein entfernter, authentisierter Angreifer kann eine Schwachstelle in Keycloak ausnutzen, um Sicherheitsvorkehrungen zu umgehen.
GHSA-m6qj-3mpp-57v8Keycloak: Insufficient verification proof scoping enables identity provider account linking attack and account compromise2026-05-20ghsa · osvUS
A flaw was found in Keycloak. The cross-session verification proof is keyed only by (local userId, idpAlias) and is not bound to the upstream identity that was actually verified, so a second upstream account on the same IdP can consume it and get linked to the victim's local account.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cert_bund nvd osv NVD CVE.org MITRE

published 2026-05-20modified 2026-07-23

references (14)

External citations — patches, advisories, analysis.

scry

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