CVE-2026-19607
Published:September 16, 2026
Updated:September 22, 2026
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.
Affected Packages
https://github.com/keycloak/keycloak.git (GITHUB):
Affected version(s) >=26.5.0 <26.6.7Fix Suggestion:
Update to version 26.6.7https://github.com/keycloak/keycloak.git (GITHUB):
Affected version(s) >=26.7.0 <26.7.4Fix Suggestion:
Update to version 26.7.4https://github.com/keycloak/keycloak.git (GITHUB):
Affected version(s) >=2.5.0.CR1 <26.4.16Fix Suggestion:
Update to version 26.4.16org.keycloak:keycloak-services (JAVA):
Affected version(s) >=2.5.0.CR1 <26.7.4Fix Suggestion:
Update to version 26.7.4Related Resources (6)
Do you need more information?
Contact UsCVSS v4
Base Score:
6.9
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
NONE
Vulnerable System Availability
LOW
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
5.3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
LOW
Weakness Type (CWE)
Improper Authentication
EPSS
Base Score:
0.51