Ticket #18007: 18007.5.patch

wp-includes/functions.php

@@ -252 +252 @@
         if ( 'N;' == $data )
                 return true;
         $length = strlen( $data );
+        // if mbstring.func_overload is enabled, strlen() may not return the full length in bytes for UTF-8 strings
+        while ( isset( $data[ $length ] ) )
+                $length++;
         if ( $length < 4 )
                 return false;
         if ( ':' !== $data[1] )
@@ -289 +292 @@
                 return false;
         $data = trim( $data );
         $length = strlen( $data );
+        // if mbstring.func_overload is enabled, strlen() may not return the full length in bytes for UTF-8 strings
+        while ( isset( $data[ $length ] ) )
+                $length++;
         if ( $length < 4 )
                 return false;
         elseif ( ':' !== $data[1] )