diff --git a/lib/SimpleSAML/Auth/LDAP.php b/lib/SimpleSAML/Auth/LDAP.php
index 005294c98240b357363f56233ea8ef406399d9fb..e16c48887382fce6d25f2139e78f999eae45cf2e 100644
--- a/lib/SimpleSAML/Auth/LDAP.php
+++ b/lib/SimpleSAML/Auth/LDAP.php
@@ -207,6 +207,7 @@ class SimpleSAML_Auth_LDAP
     {
         // Create the search filter
         $attribute = self::escape_filter_value($attribute, false);
+        $value = \SimpleSAML\Utils\Arrays::Arrayize($value);
         $value = self::escape_filter_value($value);
         $filter = '';
         foreach ($attribute as $attr) {