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.
Scoring
- Severity
- MEDIUM
- CVSS base score
- 4.3
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
- EPSS probability
- 0.35%
- CWE
- CWE-305
- Published
- 2026-05-28
- Last modified
- 2026-08-20
Affected products
- Red Hat Red Hat build of Keycloak 26.4
- Red Hat Red Hat build of Keycloak 26.4
- Red Hat Red Hat build of Keycloak 26.6
- Red Hat Red Hat build of Keycloak 26.6
Weakness type
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