CVE-2026-19607
Keycloak-services: keycloak-services: broker-originated username collision causes account lockout
- State
- Published
- Severity
- 5.3 Medium
- Published
- Sep 16, 2026
- Updated
- Sep 16, 2026
- Reserved
- Aug 12, 2026
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 5.3 Medium | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L | redhat |
Weaknesses
- CWE-287 Improper Authentication
Affected Products
| Product | Versions |
|---|---|
Red Hat build of Keycloak 26.4Red Hat |
|
Red Hat build of Keycloak 26.4Red Hat |
|
Red Hat build of Keycloak 26.4Red Hat |
|
Red Hat build of Keycloak 26.4.16Red Hat | |
Red Hat build of Keycloak 26.4.16Red Hat | |
Red Hat build of Keycloak 26.6Red Hat |
|
Red Hat build of Keycloak 26.6Red Hat |
|
Red Hat build of Keycloak 26.6Red Hat |
|
Red Hat build of Keycloak 26.6.7Red Hat | |
Red Hat build of Keycloak 26.6.7Red Hat | |
Red Hat Single Sign-On 7Red Hat |
References
- RHSA-2026:68276vendor-advisory
- RHSA-2026:68277vendor-advisory
- RHSA-2026:68278vendor-advisory
- RHSA-2026:68280vendor-advisory
- https://access.redhat.com/security/cve/CVE-2026-19607vdb-entry
- RHBZ#2514529issue-tracking
Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.