CVE-2026-16103: Red Hat Build Of Keycloak

Medium severity, CVSS 4.3. EPSS: 0.3% chance of exploitation in the next 30 days.

A flaw was found in the keycloak-services component of Keycloak. This issue is an incomplete fix for CVE-2026-9798, where brute-force protection checks were added to the Client-Initiated Backchannel Authentication (CIBA) initiation handler but were omitted from the token redemption handler. This allows an attacker with valid client credentials to obtain access and refresh tokens for a user account that has been locked due to brute-force protection, provided the authentication request was started before the lockout occurred and was approved by the user.

Affected products

• Red Hat Build Of Keycloak: affected versions not specified

Published 2026-07-17. Last modified 2026-08-31.