CVE-2026-16103

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 v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-16103	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2501736	Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:redhat:build_of_keycloak:-:*:*:*:-:*:*:*

History

No history.

Information

Published : 2026-07-17 17:17

Updated : 2026-08-31 12:17

NVD link : CVE-2026-16103

Mitre link : CVE-2026-16103

CVE.ORG link : CVE-2026-16103

JSON object : View

Products Affected

redhat

build_of_keycloak

CWE

CWE-305

Authentication Bypass by Primary Weakness

CWE-841

Improper Enforcement of Behavioral Workflow

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