A flaw was found in Keycloak, an open-source identity and access management solution. When a user account is temporarily locked due to repeated failed login attempts, an attacker with valid client credentials can exploit the Client-Initiated Backchannel Authentication (CIBA) flow to bypass this brute-force protection. This allows continued authentication attempts and token issuance even when the account should be locked, potentially enabling further unauthorized access attempts.
Fix
Patch, vendor advisory and mitigation references on NVD 2
- https://access.redhat.com/security/cve/CVE-2026-9798 Mitigation, Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2482470 Issue Tracking, Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 4.3 · redhatNVD modified 2026-10-26 12:10
Affected (CPE criteria) 1
cpe:2.3:a:redhat:build_of_keycloak:-:*:*:*:-:*:*:*
References 6
- https://access.redhat.com/errata/RHSA-2026:50846
- https://access.redhat.com/errata/RHSA-2026:50847
- https://access.redhat.com/errata/RHSA-2026:50848
- https://access.redhat.com/errata/RHSA-2026:50849
- https://access.redhat.com/security/cve/CVE-2026-9798 Mitigation, Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2482470 Issue Tracking, Vendor Advisory