CVE-2026-9798
Full vulnerability record from the local CVENow database.
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.
Severity
MEDIUM
CVSS score
4.3
(v3.1)
Vulnerability status
Modified
Source identifier
Published
2026-05-28 06:16:29.330000
Last modified
2026-10-26 12:10:00.130000
View original CVE JSON
{
"id": "CVE-2026-9798",
"sourceIdentifier": "[email protected]",
"published": "2026-05-28T06:16:29.330",
"lastModified": "2026-10-26T12:10:00.130",
"vulnStatus": "Modified",
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"value": "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."
},
{
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"value": "Se encontró una falla en Keycloak, una solución de gestión de identidad y acceso de código abierto. Cuando una cuenta de usuario se bloquea temporalmente debido a repetidos intentos fallidos de inicio de sesión, un atacante con credenciales de cliente válidas puede explotar el flujo de autenticación de canal de retorno iniciado por el cliente (CIBA) para eludir esta protección contra fuerza bruta. Esto permite intentos de autenticación continuos y emisión de tokens incluso cuando la cuenta debería estar bloqueada, lo que podría permitir intentos adicionales de acceso no autorizado."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
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"product": "Red Hat build of Keycloak 26.4",
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"metrics": {
"cvssMetricV31": [
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"source": "[email protected]",
"type": "Secondary",
"cvssData": {
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"baseScore": 4.3,
"baseSeverity": "MEDIUM",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
"userInteraction": "REQUIRED",
"scope": "UNCHANGED",
"confidentialityImpact": "LOW",
"integrityImpact": "NONE",
"availabilityImpact": "NONE"
},
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"id": "CVE-2026-9798",
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"role": "CISA Coordinator",
"version": "2.0.3"
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"weaknesses": [
{
"source": "[email protected]",
"type": "Secondary",
"description": [
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"value": "CWE-305"
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"configurations": [
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"references": [
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"url": "https://access.redhat.com/errata/RHSA-2026:50846",
"source": "[email protected]"
},
{
"url": "https://access.redhat.com/errata/RHSA-2026:50847",
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"source": "[email protected]"
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{
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"source": "[email protected]",
"tags": [
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"source": "[email protected]",
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}