CVE-2026-9801 (GCVE-0-2026-9801)
Vulnerability from cvelistv5
Published
2026-05-28 04:42
Modified
2026-06-10 21:22
CWE
  • CWE-1284 - Improper Validation of Specified Quantity in Input
Summary
A flaw was found in Keycloak. A remote attacker with high privileges, such as a realm administrator configuring a malicious Lightweight Directory Access Protocol (LDAP) server or an attacker compromising an upstream LDAP server, could exploit this vulnerability. By sending a malformed LDAP password policy response during a password authentication request, the attacker can trigger an OutOfMemoryError. This causes the Keycloak Java Virtual Machine (JVM) to terminate, leading to a denial of service (DoS) for all realms on the affected node.
References
https://access.redhat.com/errata/RHSA-2026:25097 vendor-advisory, x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:25098 vendor-advisory, x_refsource_REDHAT
https://access.redhat.com/security/cve/CVE-2026-9801 vdb-entry, x_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2482473 issue-tracking, x_refsource_REDHAT
Impacted products
Vendor Product Version
Red Hat Red Hat build of Keycloak 26.6 Unaffected: 26.6.3-3   < *
    cpe:/a:redhat:build_keycloak:26.6::el9
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   Red Hat Red Hat build of Keycloak 26.6 Unaffected: 26.6-6   < *
    cpe:/a:redhat:build_keycloak:26.6::el9
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   Red Hat Red Hat build of Keycloak 26.6 Unaffected: 26.6-6   < *
    cpe:/a:redhat:build_keycloak:26.6::el9
Create a notification for this product.
   Red Hat Red Hat build of Keycloak 26.6.3     cpe:/a:redhat:build_keycloak:26.6::el9
Create a notification for this product.
Show details on NVD website


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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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