$id = intval($_GET['id']); // Force integer type $stmt = $conn->prepare("DELETE FROM entries WHERE id = ?"); $stmt->bind_param("i", $id); $stmt->execute(); File: admin/delete_entry.php + form in admin_panel.php
$name = $_POST['name']; echo "<p>$name</p>";
$name = htmlspecialchars($_POST['name'], ENT_QUOTES, 'UTF-8'); $message = strip_tags($_POST['message'], '<b><i>'); // Allow basic formatting only echo "<p>" . htmlspecialchars($name) . "</p>"; File: admin/delete_entry.php
http://target.com/admin/delete_entry.php?id=1 OR 1=1 would delete all entries. The patch introduces multiple security layers. 4.1 Input Sanitization (XSS Fix) File: post_entry.php & view_guestbook.php