Medium severity4.9NVD Advisory· Published May 28, 2026· Updated Jun 26, 2026
CVE-2026-9801
CVE-2026-9801
Description
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.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Affected packages
Versions sourced from the GitHub Security Advisory.
| Package | Affected versions | Patched versions |
|---|---|---|
org.keycloak:keycloak-ldap-federationMaven | < 26.6.3 | 26.6.3 |
Affected products
4cpe:2.3:a:redhat:build_of_keycloak:-:*:*:*:-:*:*:*+ 1 more
- cpe:2.3:a:redhat:build_of_keycloak:-:*:*:*:-:*:*:*
- (no CPE)
Patches
Vulnerability mechanics
References
11- access.redhat.com/security/cve/CVE-2026-9801nvdMitigationVendor AdvisoryWEB
- bugzilla.redhat.com/show_bug.cginvdIssue TrackingVendor AdvisoryWEB
- github.com/advisories/GHSA-f6r7-6w34-x2gpghsaADVISORY
- nvd.nist.gov/vuln/detail/CVE-2026-9801ghsaADVISORY
- access.redhat.com/errata/RHSA-2026:25097nvdWEB
- access.redhat.com/errata/RHSA-2026:25098nvdWEB
- access.redhat.com/errata/RHSA-2026:30049nvdWEB
- access.redhat.com/errata/RHSA-2026:30050nvdWEB
- github.com/keycloak/keycloak/commit/2c4fe42235ba8c265b1da3a30541a270d5bd8c39ghsaWEB
- github.com/keycloak/keycloak/issues/49434ghsaWEB
- github.com/keycloak/keycloak/pull/49514ghsaWEB
News mentions
1- Keycloak: Twelve Vulnerabilities Disclosed, One High SeverityVypr Intelligence · May 28, 2026