---
id: CVE-2026-19607
title: >-
  A flaw was found in the first-broker-login flow of the keycloak-services
  component
summary: >-
  A flaw was found in the first-broker-login flow of the keycloak-services
  component. This component handles the initial authentication and account
  linking when a user logs in via an external identity provider. The issue
  allows an attacker…
severity: medium
cvss: 5.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L'
cwe:
  - CWE-287
vendor: Red Hat
product: keycloak-rhel9-container
affected:
  - keycloak-rhel9-container (all versions)
  - keycloak-rhel9-operator-container (all versions)
  - rhbk/keycloak-operator-bundle (all versions)
  - keycloak-services
  - rhbk-openshift-rhel9/rhbk-openshift-rhel9
  - keycloak-rhel9-container (all versions)
  - keycloak-rhel9-operator-bundle-container (all versions)
  - keycloak-rhel9-operator-container (all versions)
  - keycloak-services
  - rhbk-openshift-rhel9/rhbk-openshift-rhel9
  - keycloak-services
patched:
  - build_of_keycloak 26.4
  - build_of_keycloak 26.4.16
  - build_of_keycloak 26.6.7
published: '2026-09-16'
updated: '2026-09-16'
sourceUpdated: '2026-09-16T19:42:43.623'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-19607'
references:
  - url: 'https://access.redhat.com/errata/RHSA-2026:68276'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:68277'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:68278'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:68280'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/security/cve/CVE-2026-19607'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2514529'
    label: secalert@redhat.com
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-19607.json
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-19607'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-19607'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-16T18:25:13.980390Z'
ingestedAt: '2026-09-16T15:58:38.767Z'
epss: 0.00507
epssPercentile: 0.40695
---

## Overview

A flaw was found in the first-broker-login flow of the keycloak-services component. This component handles the initial authentication and account linking when a user logs in via an external identity provider. The issue allows an attacker to register a matching username on an external provider to trigger a collision in Keycloak, which results in the legitimate user being locked out of their account.

## Remediation

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

## Vendor advisories

- **RHSA-2026:68276** · Red Hat · fixed in: Red Hat build of Keycloak 26.4 · released 2026-09-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:68276)
- **RHSA-2026:68280** · Red Hat · fixed in: Red Hat build of Keycloak 26.4.16 · released 2026-09-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:68280)
- **RHSA-2026:68278** · Red Hat · fixed in: Red Hat build of Keycloak 26.6.7 · released 2026-09-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:68278)
- **RHSA-2026:68277** · Red Hat · fixed in: Red Hat build of Keycloak 26.6 · released 2026-09-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:68277)