CVE-2026-9087

Description

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 Vector

References

• https://access.redhat.com/security/cve/CVE-2026-9087
• https://bugzilla.redhat.com/show_bug.cgi?id=2480172