Hello, !

inject

src

<script src="hook.js"></script>
<?php
$escaped 
preg_replace("/[`()<>&#]/"""$_GET['payload']);
?>

<h1>Hello, <span id="<?= $escaped ?>"><?= htmlspecialchars($_GET['payload']) ?></span>!</h1>

<h1>inject</h1>
<form>
    <input type="text" name="payload" placeholder="your payload here">
    <input type="submit" value="GO">
</form>

<h1>src</h1>
<?php highlight_string(file_get_contents(basename(__FILE__))); ?>