Keycloak: keycloak: brute-force protection bypass in ciba flow_CVE-2026-9798

4.3 / 10

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N

Description

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.

Basic Information

ID CVE-2026-9798

Source redhat

Published May 28, 2026 at 04:37

Affected Product

Vendor Red Hat

Product Red Hat Build of Keycloak

CWE Classification

CWE-305

References

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    "published": "2026-05-28T04:37:09.472Z",
    "modified": "2026-05-28T04:37:09.472Z",
    "type": "cve",
    "title": "Keycloak: keycloak: brute-force protection bypass in ciba flow",
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