GHSA-4hx9-48xh-5mxrMediumCVSS 5.5

Keycloak LDAP User Federation provider enables admin-triggered untrusted Java deserialization

Published
December 19, 2025
Last Modified
February 17, 2026

🔗 CVE IDs covered (1)

📋 Description

A flaw was found in the Keycloak LDAP User Federation provider. This vulnerability allows an authenticated realm administrator to trigger deserialization of untrusted Java objects via a malicious LDAP server configuration.

Mitigation

Disable LDAP referrals in all LDAP user providers in all realms if projects cannot upgrade to the patched versions.

🎯 Affected products2

  • maven/org.keycloak:keycloak-ldap-federation:>= 26.3.0, < 26.4.6
  • maven/org.keycloak:keycloak-ldap-federation:< 26.2.11

🔗 References (10)