Credit Card Payments in Your Shop: Security Vulnerabilities Hardly Anyone Knows About

Credit card fraud is an abstract risk for many e-commerce operators — until it happens to them. Chargebacks, blocked payment provider accounts, fines for inadequate security standards.

Yet many of the most common attack patterns are well known and avoidable.

How attackers operate

The most common forms of attack on credit card data in e-commerce:

Skimming via malware: Malicious code is injected into the checkout page and reads card data directly as it is entered. Known as a Magecart attack — particularly prevalent in outdated Magento installations.

Credential stuffing: Stolen login combinations are tested automatically. Anyone using reused passwords is vulnerable.

Carding: Stolen card data is tested with small amounts before being used for larger purchases.

PCI-DSS: What shop operators need to know

Anyone accepting credit card payments is required to comply with the PCI-DSS standard. Most shops use payment service providers like Stripe or PayPal, which handle the bulk of the requirements. But responsibility for the checkout page lies with the shop operator.

Concretely: do not store card data in your own systems, conduct regular security reviews, keep software up to date.

Immediate measures

Three things you can do this week:

1. Update shop software — especially Magento, WooCommerce and all installed plugins
2. Set up a Content Security Policy (CSP) to block unauthorised scripts from accessing data
3. Check the payment page for external scripts — a browser audit shows which external resources are loaded during checkout

If you are unsure whether your shop meets these requirements, we can help with a brief security audit.