diff --git a/federation/ldap/src/main/java/org/keycloak/federation/ldap/idm/store/ldap/LDAPOperationManager.java b/federation/ldap/src/main/java/org/keycloak/federation/ldap/idm/store/ldap/LDAPOperationManager.java
index 215034a..8a5b299 100644
--- a/federation/ldap/src/main/java/org/keycloak/federation/ldap/idm/store/ldap/LDAPOperationManager.java
+++ b/federation/ldap/src/main/java/org/keycloak/federation/ldap/idm/store/ldap/LDAPOperationManager.java
@@ -333,6 +333,7 @@ public class LDAPOperationManager {
Hashtable<String, Object> env = new Hashtable<String, Object>(this.connectionProperties);
+ env.put(Context.SECURITY_AUTHENTICATION, LDAPConstants.AUTH_TYPE_SIMPLE);
env.put(Context.SECURITY_PRINCIPAL, dn);
env.put(Context.SECURITY_CREDENTIALS, password);