Ticket #26094: 26094.patch

src/wp-includes/formatting.php

@@ -844 +844 @@
         $special_chars = array("?", "[", "]", "/", "\\", "=", "<", ">", ":", ";", ",", "'", "\"", "&", "$", "#", "*", "(", ")", "|", "~", "`", "!", "{", "}", chr(0));
         $special_chars = apply_filters('sanitize_file_name_chars', $special_chars, $filename_raw);
         $filename = str_replace($special_chars, '', $filename);
-        $filename = preg_replace('/[\s-]+/', '-', $filename);
+        $filename = preg_replace('/[\p{Z}\s-]+/u', '-', $filename); // Match all UTF-8 whitespace
         $filename = trim($filename, '.-_');
 
         // Split the filename into a base and extension[s]
@@ -864 +864 @@
         foreach ( (array) $parts as $part) {
                 $filename .= '.' . $part;
 
-                if ( preg_match("/^[a-zA-Z]{2,5}\d?$/", $part) ) {
+                if ( preg_match("/^[a-zA-Z]{2,5}\d?$/u", $part) ) {
                         $allowed = false;
                         foreach ( $mimes as $ext_preg => $mime_match ) {
                                 $ext_preg = '!^(' . $ext_preg . ')$!i';