Description:
------------
When you call this code will immediately crash the server itself .

Test script:
---------------
<?php
$phar = new Phar("A:A:.phar");
$phar[hello_habr.txt] = '<? Hello Habr!?>';
?>

or web

<?php
phpinfo();
$phar = new Phar($_GET[a].".phar");
$phar[hello_habr.txt] = '<? Hello Habr!?>';
?>

http://localhost/1.php?a=A:A: