CVE-2026-9087

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 v3 6.4 MEDIUM

6.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.2 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:25097
https://access.redhat.com/errata/RHSA-2026:25098
https://access.redhat.com/errata/RHSA-2026:30049
https://access.redhat.com/errata/RHSA-2026:30050
https://access.redhat.com/security/cve/CVE-2026-9087	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2480172	Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:redhat:build_of_keycloak:-:*:*:*:-:*:*:*

History

No history.

Information

Published : 2026-05-20 17:16

Updated : 2026-07-23 12:10

NVD link : CVE-2026-9087

Mitre link : CVE-2026-9087

CVE.ORG link : CVE-2026-9087

JSON object : View

Products Affected

redhat

build_of_keycloak

CWE

CWE-639

Authorization Bypass Through User-Controlled Key

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