Ecommerce Security

The Payment Card Industry Data Security Standard (PCI DSS) is a set of security requirements mandatory for any entity that processes, stores or transmits card payment data. It has four compliance levels based on transaction volume, but the basic requirements apply to everyone.

The simplest way to comply with PCI DSS is to never handle card data directly. Payment gateways like Stripe, Adyen or PayPal process payments on their infrastructure, relieving you of most requirements. If you tokenise card data with Stripe Elements or similar, your compliance level is reduced to a Self-Assessment Questionnaire (SAQ-A).

Ecommerce fraud evolves constantly. The most common tactics include stolen card use, chargeback fraud and mass creation of fake accounts. Fraud costs include not only direct losses but also chargeback fees and potential penalties from payment networks.

Tools like Stripe Radar, Signifyd or Riskified use machine learning to evaluate the risk of each transaction in real time. Complement these tools with custom rules based on your store’s behaviour: unusual orders, suspicious shipping addresses or anomalous purchasing patterns.

Ecommerce user accounts are targets for credential stuffing attacks: massive lists of credentials leaked from other services are automatically tested against your login form. If a user reuses the same password, their account is compromised.

Implement aggressive rate limiting on login and registration endpoints. Offer two-factor authentication (2FA) as an option for customers and make it mandatory for administrators. Monitor logins from unusual locations or devices and notify the user.

Checkout is the most critical point in the conversion funnel and also the most sensitive in terms of security. A checkout that does not convey trust generates abandonment; an insecure checkout generates breaches.

Beyond payment data, an ecommerce site handles personal information protected by GDPR and other regulations: addresses, purchase history, preferences and communications. All this information must be encrypted at rest and in transit.

Use AES-256 for encryption at rest and TLS 1.3 for encryption in transit. Apply the data minimisation principle: do not collect or store information you do not need to operate. Implement clear retention policies and automated purge mechanisms.

An ecommerce site requires 24/7 monitoring for suspicious activity. Fraudulent transactions, unauthorised access attempts and unexpected changes to critical files should trigger immediate alerts.

Document an ecommerce-specific incident response plan covering: notification to affected customers, communication with the payment gateway, forensic evidence preservation and notification to the data protection authority if GDPR applies.