diff --git a/CHANGELOG b/CHANGELOG
index a53afbf5f..bd42a5545 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -50,6 +50,7 @@ CHANGELOG Roundcube Webmail
 - Fix redundant blank lines when using HTML and top posting (#1490576)
 - Fix redundant blank lines on start of text after html to text conversion (#1490577)
 - Fix HTML sanitizer to skip <!-- node type X --> in output (#1490583)
+- Fix invalid LDAP query in ACL user autocompletion (#1490591)
 
 RELEASE 1.1.3
 -------------
diff --git a/plugins/acl/acl.php b/plugins/acl/acl.php
index 0393a3d68..252668391 100644
--- a/plugins/acl/acl.php
+++ b/plugins/acl/acl.php
@@ -739,7 +739,11 @@ class acl extends rcube_plugin
         $config['fieldmap']['uid']  = $uid_field;
 
         // search in UID and name fields
-        $config['search_fields']   = array_values($config['fieldmap']);
+        // $name_field can be in a form of <field>:<modifier> (#1490591)
+        $name_field = preg_replace('/:.*$/', '', $name_field);
+        $search     = array_unique(array($name_field, $uid_field));
+
+        $config['search_fields']   = $search;
         $config['required_fields'] = array($uid_field);
 
         // set search filter