diff --git a/phpBB/phpbb/db/driver/mysqli.php b/phpBB/phpbb/db/driver/mysqli.php
index 457e6d8ac8..faaa20b339 100644
--- a/phpBB/phpbb/db/driver/mysqli.php
+++ b/phpBB/phpbb/db/driver/mysqli.php
@@ -336,7 +336,10 @@ class mysqli extends \phpbb\db\driver\mysql_base
 	*/
 	function sql_escape($msg)
 	{
-		return @mysqli_real_escape_string($this->db_connect_id, $msg);
+		return @mysqli_real_escape_string(
+			$this->db_connect_id,
+			utf8_encode_ucr($msg)
+		);
 	}
 
 	/**