CVE-2026-9798

A flaw was found in Keycloak, an open-source identity and access management solution. When a user account is temporarily locked due to repeated failed login attempts, an attacker with valid client credentials can exploit the Client-Initiated Backchannel Authentication (CIBA) flow to bypass this brute-force protection. This allows continued authentication attempts and token issuance even when the account should be locked, potentially enabling further unauthorized access attempts.

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/errata/RHSA-2026:50846
https://access.redhat.com/errata/RHSA-2026:50847
https://access.redhat.com/errata/RHSA-2026:50848
https://access.redhat.com/errata/RHSA-2026:50849
https://access.redhat.com/security/cve/CVE-2026-9798	Mitigation Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2482470	Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-05-28 06:16

Updated : 2026-08-20 01:16

NVD link : CVE-2026-9798

Mitre link : CVE-2026-9798

CVE.ORG link : CVE-2026-9798

JSON object : View

Products Affected

redhat

build_of_keycloak

CWE

CWE-305

Authentication Bypass by Primary Weakness

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