For massive traffic spikes, offloading transient cart numbers to a high-speed in-memory database like Redis keeps the main relational database from locking up under heavy input/output operations.
is a positive integer to prevent errors or malicious "zero" or "negative" quantity entries. Implementation Methods
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 ). add-cart.php num
<?php session_start();
header('Location: cart.php'); exit;
Implementing this functionality requires a frontend form (HTML), backend processing (PHP), and session management. 1. The Frontend (HTML Form)
// Secure database verification using PDO prepared statements $stmt = $pdo->prepare('SELECT price, stock_status FROM products WHERE id = :id AND status = "active"'); $stmt->execute(['id' => $product_id]); $product = $stmt->fetch(); if (!$product) // Handle invalid or inactive product die('Product not available.'); Use code with caution. 3. Request Method Vulnerabilities (GET vs. POST) Course Hero In this context
The phrase "add-cart.php?num=" is a common URL structure used in custom PHP shopping cart scripts to add a specific item to a user's session-based basket. Course Hero In this context, typically refers to the unique Product ID item number being added. Course Hero Typical Usage
If you do not implement strict numerical controls over incoming data parameters like product_id and quantity , your platform faces high risks. Attackers can leverage these flaws for logic exploitation, price manipulation, and SQL injection attacks. and SQL injection attacks.