Description
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
redhat: build of keycloak
References4
- access.redhat.com/security/cve/CVE-2026-16103 Vendor Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2501736 Issue TrackingVendor Advisory
- access.redhat.com/errata/RHSA-2026:95761
- access.redhat.com/errata/RHSA-2026:95762
Metrics
- CVSS 3.1
-
4.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N - EPSS — exploit probability
- 0% percentile: 38 · as of 15 November 2026
- CWE
- CWE-305CWE-841
Could this be exploited in your environment?
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