---
id: CVE-2026-9798
title: >-
  A flaw was found in Keycloak, an open-source identity and access management
  solution
summary: >-
  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-Initi…
severity: medium
cvss: 4.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N'
cwe:
  - CWE-305
vendor: redhat
product: build_of_keycloak
affected:
  - build_of_keycloak
published: '2026-05-28'
updated: '2026-08-05'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-9798'
references:
  - url: 'https://access.redhat.com/errata/RHSA-2026:50846'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:50847'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:50848'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:50849'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/security/cve/CVE-2026-9798'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2482470'
    label: secalert@redhat.com
tags:
  - nvd
epss: 0.0049
epssPercentile: 0.39503
ingestedAt: '2026-08-06T06:56:50.725Z'
---

## Overview

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.

## Affected

- `build_of_keycloak`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.