CVE-2026-9801
mediumpriority · track · 0EPSS 0.005 · 41 %ileDEEUUSEPSS · scored 2026-10-27
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
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (12)
Products and version ranges known to be affected.
- Maven org.keycloak:keycloak-ldap-federation< 26.6.3osvUSpkg:maven/org.keycloak/keycloak-ldap-federation
advisories (2)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-1708Keycloak: Mehrere SchwachstellenDeutsch2026-05-27csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Keycloak ausnutzen, um seine Privilegien zu erhöhen, um Informationen offenzulegen, um Sicherheitsvorkehrungen zu umgehen und um einen Denial of Service Angriff durchzuführen.
- GHSA-f6r7-6w34-x2gpKeycloak Vulnerable to Improper Validation of Specified Quantity in Input2026-05-28ghsa · osvUS
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.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (14)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/CVE-2026-9801cnnvd
- https://bugzilla.redhat.com/show_bug.cgi?id=2482473cnnvd
- https://access.redhat.com/errata/RHSA-2026:25097enisa_euvd
- https://access.redhat.com/errata/RHSA-2026:25098enisa_euvd
- https://access.redhat.com/errata/RHSA-2026:30049enisa_euvd
- https://access.redhat.com/errata/RHSA-2026:30050enisa_euvd
- https://access.redhat.com/security/cve/CVE-2026-9801enisa_euvd
- https://bugzilla.redhat.com/show_bug.cgi?id=2482473enisa_euvd
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