Keycloak: keycloak: denial of service via malformed ldap password policy response
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 4.9epss 0.5%
exploitation probability
0.5%top 61% of all CVEs
observed exploitation
nono source reports it
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.
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Affected products
Red Hat · Red Hat build of Keycloak 26.4Red Hat · Red Hat build of Keycloak 26.4.13Red Hat · Red Hat build of Keycloak 26.6Red Hat · Red Hat build of Keycloak 26.6.3References
https://access.redhat.com/errata/RHSA-2026:25097https://access.redhat.com/errata/RHSA-2026:25098https://access.redhat.com/errata/RHSA-2026:30049https://access.redhat.com/errata/RHSA-2026:30050https://access.redhat.com/security/cve/CVE-2026-9801https://bugzilla.redhat.com/show_bug.cgi?id=2482473