CVE-2026-19607
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.
Does this matter?
Lower severity and a low EPSS score (0.69%). Track it; it rarely justifies an emergency change on its own.
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.
- CVSS 3.1
- 5.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- EPSS
- 0.69% probability · 52th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-287
- Source
- secalert@redhat.com
EPSS 0.7% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.