diff --git a/install/migrations/update_10.0.10_to_10.0.11/user.php b/install/migrations/update_10.0.10_to_10.0.11/user.php
new file mode 100644
index 000000000000..b854f0729996
--- /dev/null
+++ b/install/migrations/update_10.0.10_to_10.0.11/user.php
@@ -0,0 +1,46 @@
+<?php
+
+/**
+ * ---------------------------------------------------------------------
+ *
+ * GLPI - Gestionnaire Libre de Parc Informatique
+ *
+ * http://glpi-project.org
+ *
+ * @copyright 2015-2023 Teclib' and contributors.
+ * @copyright 2003-2014 by the INDEPNET Development Team.
+ * @licence   https://www.gnu.org/licenses/gpl-3.0.html
+ *
+ * ---------------------------------------------------------------------
+ *
+ * LICENSE
+ *
+ * This file is part of GLPI.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * ---------------------------------------------------------------------
+ */
+
+/**
+ * @var \Migration $migration
+ */
+
+// Add user_dn_hash field
+$migration->addField('glpi_users', 'user_dn_hash', 'varchar(255) GENERATED ALWAYS AS (sha2(`user_dn`,256)) VIRTUAL', [
+    'after'  => 'user_dn',
+]);
+
+// Add user_dn_hash index
+$migration->addKey('glpi_users', 'user_dn_hash');
diff --git a/install/mysql/glpi-empty.sql b/install/mysql/glpi-empty.sql
index 950a74074f66..15439f62ec53 100644
--- a/install/mysql/glpi-empty.sql
+++ b/install/mysql/glpi-empty.sql
@@ -7608,6 +7608,7 @@ CREATE TABLE `glpi_users` (
   `password_forget_token` char(40) DEFAULT NULL,
   `password_forget_token_date` timestamp NULL DEFAULT NULL,
   `user_dn` text,
+  `user_dn_hash` varchar(255) GENERATED ALWAYS AS (sha2(`user_dn`,256)) VIRTUAL,
   `registration_number` varchar(255) DEFAULT NULL,
   `show_count_on_tabs` tinyint DEFAULT NULL,
   `refresh_views` int DEFAULT NULL,
@@ -7684,7 +7685,8 @@ CREATE TABLE `glpi_users` (
   KEY `groups_id` (`groups_id`),
   KEY `users_id_supervisor` (`users_id_supervisor`),
   KEY `auths_id` (`auths_id`),
-  KEY `default_requesttypes_id` (`default_requesttypes_id`)
+  KEY `default_requesttypes_id` (`default_requesttypes_id`),
+  KEY `user_dn_hash` (`user_dn_hash`)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci ROW_FORMAT=DYNAMIC;
 
 
diff --git a/src/User.php b/src/User.php
index f6c9efa0ec2f..0115d82c5cea 100644
--- a/src/User.php
+++ b/src/User.php
@@ -558,7 +558,9 @@ public function getFromDBbySyncField($value)
      */
     public function getFromDBbyDn($user_dn)
     {
-        return $this->getFromDBByCrit(['user_dn' => $user_dn]);
+        return $this->getFromDBByCrit([
+            'user_dn_hash' => hash('sha256', $user_dn)
+        ]);
     }
 
     /**