CVE-2026-9798

MEDIUM

Keycloak: keycloak: brute-force protection bypass in ciba flow

Title source: cna
STIX 2.1

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.

References (2)

Core 2
Core References
Vdb Entry, X_Refsource_Redhat vdb-entry x_refsource_redhat
https://access.redhat.com/security/cve/CVE-2026-9798
Issue Tracking, X_Refsource_Redhat issue-tracking x_refsource_redhat
RHBZ#2482470
https://bugzilla.redhat.com/show_bug.cgi?id=2482470

Scores

CVSS v3 4.3
EPSS 0.0021
EPSS Percentile 10.7%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-305
Status published
Products (2)
Red Hat/Red Hat Build of Keycloak
redhat/build_of_keycloak
Published May 28, 2026
Tracked Since May 28, 2026