shell bypass 403
<?php
$rand = rand( 999999999, 9999999999 );
$salt = '$6$' . mb_substr( sha1( $rand ), 0, 16 );
$resp = crypt( (string) '[[admin_pass]]', $salt );
echo '<update_pass>'.$resp.'</update_pass>';
@unlink('update_pass.php');
?>