Medium 4.3Published Jul 17, 2026

CVE-2026-16103Keycloak-services: keycloak-services: incomplete fix for ciba brute-force lockout bypass at token redemption

Updated under an hour ago (Oct 27, 2026, 10:50 AM ET)

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It affects Red Hat Build of Keycloak and 4 other products. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for Red Hat Build of Keycloak

Exploited in the last 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.

CVSS: 4.3 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
Weakness (CWE): CWE-305, CWE-841
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: redhat
NVD analysis: Modified
Record last updated: Aug 31, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Red Hat Red Hat Build of Keycloak redhat:build_keycloak	All versions	CNA record
Red Hat Red Hat Data Grid 8 redhat:jboss_data_grid	8	CNA record
Red Hat Red Hat JBoss Enterprise Application Platform Expansion Pack redhat:jbosseapxp	Versions not stated	CNA record
Red Hat Red Hat Single Sign-On 7 redhat:red_hat_single_sign_on	7	CNA record
redhat build_of_keycloak redhat:build_of_keycloak	all versions	NVD

References

References

https://access.redhat.com/security/cve/CVE-2026-16103	vdb-entry, x-refsource-redhat, vendor-advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2501736	issue-tracking, x-refsource-redhat, vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.