CVE-2026-9798

medium

Description

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.

References

https://bugzilla.redhat.com/show_bug.cgi?id=2482470

https://access.redhat.com/security/cve/CVE-2026-9798

Details

Source: Mitre, NVD

Published: 2026-05-28

Updated: 2026-05-28

Risk Information

CVSS v2

Base Score: 5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:N

Severity: Medium

CVSS v3

Base Score: 4.3

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N

Severity: Medium

EPSS

EPSS: 0.00053