CVE-2026-19607mediumCWE-287

CVE-2026-19607: medium-severity vulnerability in Red Hat build of Keycloak 26.4

Keycloak-services: keycloak-services: broker-originated username collision causes account lockout

Published

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33Vexday Risk Score

No sign of exploitation. It has a public proof of concept.

ssvc Attendcvss 5.3epss 0.7%
from disclosure to weaponsame day
Published on NVDSep 16
1st PoCAug 8
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Affected products
Red Hat · Red Hat build of Keycloak 26.4Red Hat · Red Hat build of Keycloak 26.4.16Red Hat · Red Hat build of Keycloak 26.6Red Hat · Red Hat build of Keycloak 26.6.7Red Hat · Red Hat Single Sign-On 7
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
Related CVEs — Red Hat build of Keycloak 26.4

In the same product, most dangerous first.

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