Add-cart.php Num Work Jun 2026
For persistent carts that remain across different devices or sessions, add-cart.php
// ... Logic continues below
: The file add-cart.php is often listed in security "fuzzing" databases (like FuzzDB and SecLists ), meaning it is a common target for automated vulnerability scanners.
The most common exploitation method for the num parameter involves or Logic Errors . add-cart.php num
: Always ensure the ID and num are integers to prevent SQL injection or malicious inputs.
If a developer forgets to validate that num is a positive number, an attacker can intentionally pass a negative value (e.g., add-cart.php?id=101&num=-5 ).
Even if a negative number slips into the cart database, the final checkout script must enforce business rules: For persistent carts that remain across different devices
is a positive integer to prevent errors or malicious "zero" or "negative" quantity entries. Implementation Methods
86400, 'cookie_secure' => true, // Force HTTPS 'cookie_httponly' => true, // Mitigate XSS cookie theft 'cookie_samesite' => 'Lax' ]); // Ensure the session cart structure exists if (!isset($_SESSION['cart'])) $_SESSION['cart'] = []; // 2. Class definition for clean data encapsulation class CartManager private array $dbConnectionPool; // Placeholder for real DB verification /** * Safely add or update an item within the user's session cart. */ public function addItem(int $productId, int $quantity): array // Enforce physical constraints: you cannot buy 0 or negative items if ($quantity <= 0) return [ 'success' => false, 'message' => 'Invalid item count. Quantity must be 1 or greater.' ]; // Optional: Perform a database check here to verify $productId exists and is in stock // e.g., SELECT stock_qty FROM products WHERE id = ? // If product already exists in the cart, increment its quantity; otherwise, set it if (isset($_SESSION['cart'][$productId])) $_SESSION['cart'][$productId] += $quantity; else $_SESSION['cart'][$productId] = $quantity; return [ 'success' => true, 'message' => 'Cart updated successfully.', 'total_items' => array_sum($_SESSION['cart']) ]; // 3. Request processing and sanitation header('Content-Type: application/json'); // Accept both GET (for simple links) and POST (preferred for forms/AJAX) $rawProductId = $_REQUEST['id'] ?? null; $rawNum = $_REQUEST['num'] ?? null; // The target "num" parameter // Reject requests missing essential parameters if ($rawProductId === null || $rawNum === null) http_response_code(400); echo json_encode(['success' => false, 'message' => 'Missing product ID or quantity parameter (num).']); exit; // Sanitize inputs by casting them explicitly to integers $productId = (int)$rawProductId; $num = (int)$rawNum; // 4. Execution $cartManager = new CartManager(); $response = $cartManager->addItem($productId, $num); if (!$response['success']) http_response_code(422); // Unprocessable Entity echo json_encode($response); exit; Use code with caution.
// Redirect back to previous page or product page $redirect = isset($_SERVER['HTTP_REFERER']) ? $_SERVER['HTTP_REFERER'] : 'products.php'; header("Location: $redirect"); exit; ?> : Always ensure the ID and num are
This specific file name and parameter string ( add-cart.php?num= ) are frequently cited in "Google Dorks" or lists used for identifying common web application paths for testing vulnerabilities. Security researchers and developers use these patterns to locate scripts that might be susceptible to if the num parameter is not properly sanitized or bound before being used in a query. A Shopping Cart using PHP Sessions - PHP Web Applications
// Example AJAX call (using fetch) function updateQuantity(productId, newQuantity) fetch(`update-cart.php?id=$productId&num=$newQuantity`) .then(response => response.json()) .then(data => console.log('Cart updated', data); // Update subtotal using JS ); Use code with caution.
The attacker crafts add-cart.php?num=12 AND 1=2 UNION SELECT database()-- - . The cart page inadvertently displays the database name (e.g., "vintage_store_db") because the product name lookup fails and falls back to the error message.