CVE-2026-9798CWE-305

CVE-2026-9798

Medium · published May 28, 2026

CVSS v3.1
4.3
EPSS
0%
Percentile
41.2
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
4.3 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
CVSS v4.0
Not supplied
EPSS
0.00490 · 41.2th percentile
Weakness
CWE-305 · Authentication Bypass by Primary Weakness
Published
2026-05-28T10:16Z
Affected products (1)
ProductVersionsFixed in
redhat/build_of_keycloakall versions—
References (6)
EPSS history
Timeline
  • 28 MAY 04:37Z
    Keycloak: keycloak: brute-force protection bypass in ciba flow
    cvelistv5