Ecommerce Security: Threats and Best Practices

Every time a customer enters their card details at checkout, they’re trusting your store with data that’s valuable to attackers. Ecommerce security is everything you do to earn and keep that trust.

The value of ecommerce losses due to online payment fraud worldwide is predicted to grow to more than $131 billion by 2030. According to LexisNexis, every dollar lost to fraud actually costs US store owners an average of $4.61 when you factor in financial and operational consequences. If you’re running on thin margins, sustained fraud has big implications.

This guide covers the most common ecommerce security threats, the real cost of security failures, and the best practices every store owner should have in place.

What is ecommerce security?

Ecommerce security is the set of measures that protect online stores and their customers from fraud, data theft, and unauthorized access. It covers payment processing, account authentication, customer data storage, and the technology layer the store runs on.

Ecommerce security is distinct from general website security. Stores handle financial data, such as card numbers, billing addresses, and transaction histories, that have direct monetary value to attackers. Store owners are also held to formal compliance standards by the payment industry, regardless of their company’s size.

Why it’s different on a hosted platform vs. self-hosted

On a self-hosted platform, security is the store owner’s responsibility. That means doing ongoing technical work like sourcing and renewing SSL/TLS certificates, achieving payment card industry (PCI) compliance, patching server software, and configuring firewalls. 

PCI compliance alone costs small businesses $1,000 to $10,000 a year depending on how many transactions they make. 

With a host platform like Shopify, PCI compliance, certificates, network security, and any server maintenance is handled at the platform level, rather than the store level. You still have security responsibilities as a store owner, but you don’t have to build them from scratch.

The shared responsibility model

Security on any hosted platform is a two-way arrangement: 

• Shopify. Secures the infrastructure, including the servers, the payment processing systems, the checkout, and the software that everything runs on. 
• Store owners. Secure their accounts and operations, including login credentials, the third-party apps they install, how they handle sensitive customer data, and who on their team has access to the admin.

Both host platforms and store owners have to do their part to create security measures. Shopify can’t protect a store whose admin password is "password123," or whose owner clicks a phishing link and hands over their credentials, just as a store owner can’t patch the servers their store runs on, because those belong to Shopify. 

Common ecommerce security threats

Online stores face a specific set of threats, mostly targeting payment data and customer accounts. Here’s what store owners are most likely to encounter.

Payment fraud and card testing attacks

Payment fraud occurs when a transaction is made without the cardholder’s knowledge or consent. Ecommerce transactions in particular are vulnerable to card-not-present (CNP) fraud, where the physical card is never verified. According to Juniper Research, online payment fraud will exceed $362 billion between 2023 and 2028. 

In CNP fraud, fraudsters gain access to credit card information through data breaches, phishing attacks, or skimming devices. To test cards, they then run small online transactions to validate stolen card numbers before using them for larger fraud. Once a card is validated, the sensitive data can either be used directly or sold on dark web markets. 

Phishing, account takeover, and credential stuffing

Large-scale data breaches provide fuel for account takeover fraud (offsite), or ATO, attacks. Attackers take exposed username/password combinations and systematically test them automatically across other sites. They might also use breached data to support more targeted phishing schemes.

Phishing is the practice of sending fake emails, texts, or calls that impersonate a trusted source to trick recipients into handing over their login credentials or credit card details. In IBM’s 2025 Cost of a Data Breach Report, phishing was the single most common way attackers got in, responsible for 16% of all breaches studied.

When attackers gain unauthorized access to a legitimate customer’s account, it’s considered account takeover fraud. Account takeover fraud affected six million consumers in 2025, an 18% increase from 2024, with losses reaching $17 billion in 2025.

Bot attacks and DDoS

Bots are automated scripts that interact with a store’s website or application programming interface (API) at machine speed. In ecommerce, they’re used to run card testing attacks, scrape pricing data, create fake accounts, and stockpile high-demand products before real shoppers can buy them. 

According to the 2025 Imperva Bad Bot Report, 44% of advanced bot traffic now targets API endpoints, which handle checkout, inventory, and customer account data.

DDoS (distributed denial-of-service) attacks work by using malicious software to flood a store with traffic so that real customers can’t gain access. 

Shopify Sidekick demonstrated the real-world impact of early bot detection when it flagged a major bot attack on Maggy London’s storefront before any other monitoring system. 

Data breaches and skimming malware

A data breach happens when unauthorized parties access stored customer data. The global average cost of a data breach in 2025 was $4.4 million. For US businesses, that figure reached a record $10.22 million, the highest in the world.

Digital skimming (sometimes called Magecart attacks) results when attackers copy the debit or credit card information a customer enters during checkout. Skimming malware injects malicious code into a store’s checkout page to capture card details as customers type them. These brute force attacks target JavaScript and can be difficult to spot if you don’t run regular code audits. 

Hosted platforms like Shopify are significantly less exposed to this kind of attack than self-hosted stores because store owners can’t modify the underlying checkout code.

The real cost of ecommerce security failures

A single incident can trigger a chargeback bill, a regulatory fine, and a wave of customer cancellations, sometimes all at once.

Chargebacks

A chargeback happens when a customer disputes a transaction with their bank, the bank reverses the charge, and the store loses both the product, the revenue, and a dispute fee from the payment processor.

The global value of chargebacks is predicted to reach $46.1 billion in 2029, with each chargeback costing store owners an average of $128 in third-party fees and internal costs, 

Most processors flag stores whose chargeback rate is higher than 0.9%. Above 1%, processors can stop accepting cards completely. Maine Lobster Now saw their chargeback rate hit 0.25% of total transactions before switching to Shopify Payments with integrated fraud management. Since switching, chargebacks due to fraud have fallen to 0.025%, a 93% reduction.

“I used to have an agent, and almost her whole job was fraud,” says Julian Klenda, CEO of Maine Lobster Now. “Now she doesn’t have to deal with that anymore. She’s able to focus her time on enhancing customer experience, especially with our bigger customers, making sure everything is the way they want.”

Regulatory fines and GDPR exposure

If you’re selling to customers in the EU and UK, the General Data Protection Regulation (GDPR) applies, regardless of where your store is based. European supervisory authorities issued approximately €1.2 billion in GDPR fines in 2025, with per-day breach notifications rising 22% year-over-year to an average of 443 per day. 

Serious GDPR violations carry fines of up to 4% of a company’s global annual revenue. There’s also the cost of the breach itself, a potential regulatory fine on top, and possible compensation claims from affected customers.

Customer trust and conversion impact

Security failures have long-tail effects on customer behavior. According to Sift’sQ3 2025 Digital Trust Index, 75% of consumers say they would stop using a site after experiencing an account takeover there, and 87% would share the experience with others. 

Modern browsers now flag any site without HTTPS with a “Not secure” warning in the address bar, which is visible to customers when they’re deciding whether to enter their card details. 

Shopify’s built-in security protections

Store owners that use Shopify get access to ecommerce security measures by default, rather than having to worry about sourcing and managing security tools on their own.

PCI compliance, SSL/TLS, and HTTPS

Every Shopify store is PCI DSS-compliant by default. PCI DSS (Payment Card Industry Data Security Standard) is the global security baseline for any online business that accepts card payments. 

Managing PCI DSS compliance independently means completing annual self-assessments, running quarterly vulnerability scans, and potentially paying for a formal audit by a Qualified Security Assessor (QSA). 

Every Shopify store also gets a free Transport Layer Security (TLS) certificate automatically, with HTTPS switched on by default, and all card readers are PCI and Europay, Mastercard, and Visa (EMV) compliant. 

Fraud analysis: how Shopify scores every order

Shopify’s fraud analysis runs on every order placed through a Shopify store. The system uses machine learning to assess risk across multiple signals: 

• Address verification (AVS) checks
• Card Verification Value (CVV) verification
• Internet Protocol (IP) address data
• Proxy detection
• Unusual purchase patterns 

Each order receives a low, medium, or high risk rating.

After switching to Shopify, Winter Park Cycles recorded $600,000 in sales with zero chargebacks across around 1,000 orders in the first 90 days.

“We haven’t had one chargeback out of 700 orders in the past two months,” says Ward Bates, owner of Winter Park Cycles. “I think Shopify’s fraud notification system does a much better job screening ahead of time.” 

Shopify Flow connects directly to fraud analysis, so you can build automated workflows based on risk scores that auto-capture low-risk orders, hold high-risk ones for review, or cancel flagged orders automatically.

Shopify Protect: guaranteed chargeback coverage

Shopify Protect (formerly Fraud Protect) is available to eligible Shopify Payments users in the US. Shopify marks orders as protected, which guarantees payment and automatically handles chargebacks. If a dispute is filed on a protected order, Shopify covers the chargeback and the dispute fee.

“Fraud Control allowed us to prevent fraudulent transactions and block them based on the risk to avoid Chargeback. With Shopify Payments, we saved transaction costs and simplified the checkout process for customers,” says Alessandro Labozzetta, ecommerce project manager at Profumerie Griffe.

Dynamic 3D Secure checkout

Shopify Payments uses dynamic 3D Secure (3DS), which is an extra verification step that appears for higher-risk transactions. 

When a cardholder completes that verification, the responsibility for any fraudulent chargeback moves from the store to the card issuer. That means Visa and Mastercard disputes on 3DS–authenticated transactions are no longer the store’s financial problem.

Only 32.4% of store owners currently implement 3DS. Shopify Payments applies it dynamically, so it appears on high-risk transactions without bogging down legitimate checkouts.

Ecommerce security best practices for store owners

Shopify handles platform-level security, but store owners have their own responsibilities. Here’s what you can do. 

Enable two-step authentication and use passkeys

You need two-step authentication (2FA) to use Shopify Payments, but you should enable it for all admin accounts, not just payment-related ones. Shopify supports passkeys as an additional authentication layer.

To enable 2FA in the Shopify admin: go to your profile, select Manage account, and follow the two-step authentication setup under Security.

Configure fraud prevention rules in Shopify Payments

You can configure fraud prevention settings with Shopify Payments by setting up AVS and CVV verification requirements, and choosing how the checkout handles mismatched billing addresses. 

To access these settings go to Settings → Payments → Shopify Payments → Manage → Fraud prevention.

Note that AVS is deactivated by default in Shopify Payments because fraud analysis handles high-risk transactions separately. Enabling AVS alongside fraud analysis can sometimes bump up false declines on legitimate orders so review your order risk reports before changing defaults.

Use Shopify Flow to automate high-risk order handling

Shopify Flow lets you build automated workflows that automatically respond to fraud analysis risk scores. Common configurations include:

• Auto-capturing low-risk orders
• Adding high-risk orders to a manual review queue
• Sending internal notifications for medium-risk orders
• Canceling orders that match specific fraud patterns

To set up fraud workflows go to Apps → Shopify Flow, and select the relevant order risk triggers. The Shopify Help Center includes a library of pre-built fraud workflow templates.

Train your team to spot phishing and social engineering

Attackers now use generative artificial intelligence (AI) to craft convincing, personalized messages that pass basic grammar and formatting checks.

Team training should cover how to identify suspicious sender domains, how to verify requests for credential changes or payment redirects, and how they can report suspicious emails. Shopify’s security guidance covers phishing, vishing (voice), and smishing (SMS) protection.

Keep apps and third-party integrations audited

Every app installed in a Shopify store can access order data, customer information, or store settings depending on the permissions you give it when you install it. 

Regularly review which apps have access to your store, and remove any that are no longer in use. To audit apps go to Settings → Apps and sales channels and check the permissions listed for each installed app.

When selecting new apps, prioritize apps with “Built for Shopify” status and review scores above 3.75. These apps have been reviewed against Shopify’s technical requirements and are maintained to current platform standards.

Payment security: gateways, PCI, and what store owners need to know

Payment security has its own set of standards and terminology. Here’s a breakdown of what to focus on. 

What PCI DSS actually means for your store

PCI DSS has 12 core requirements covering network security, encryption, access controls, monitoring, and security policies. They apply to every business that accepts card payments, regardless of your size. 

Most small ecommerce stores fall into Level 4, which describes stores that process fewer than 20,000 transactions per year. If this is you, it means you need to complete an annual self-assessment questionnaire (SAQ) rather than undergoing a formal third-party audit.

On Shopify, PCI compliance is handled at the platform level. Shopify processes and stores card data in a PCI DSS–compliant environment, which means you don’t need to manage it yourself. Your responsibility is to operate your store in a way that doesn’t introduce non-compliant data handling. In practice, that means not asking customers for their card details outside of checkout, and never storing card numbers in order notes, emails, or spreadsheets.

AVS, CVV, and 3D Secure

These are three verification tools that catch fraud before a transaction goes through: 

• AVS (Address Verification System). Checks whether the billing address provided matches the one on file with the card issuer. 
• CVV (Card Verification Value). The three- or four-digit security code on a card; asking for a CVV makes it harder for attackers using stolen card numbers to complete a transaction without physical access to the card.
• 3DS (3D Secure). Adds a multifactor authentication step in the form of a one-time code or biometric for higher-risk transactions. 

Choosing a payment gateway with the right security standards

The security of a payment gateway determines how card data is handled at checkout. When choosing a gateway, check that it’s PCI DSS–certified at the processor level, has tokenization (replacing card data with a non-sensitive token), and supports 3DS 2.0 authentication.

Shopify Payments is built into Shopify, PCI-compliant by default, and includes fraud analysis, 3D Secure, and Shopify Protect for eligible stores. Third-party payment gateways can be used with Shopify stores, but bring their own compliance and security requirements. Check certifications directly with the provider before you commit.

How to build customer trust through visible security signals

Security isn’t just about preventing attacks. The right signals at the right moment in the shopping journey give customers the confidence to complete a purchase.

SSL padlock, Shop Pay recognition, and trust badges

The padlock icon and HTTPS prefix in a browser address bar are the most widely recognized security signals for online shoppers. As of June 2026, 98% of US web traffic on Google’s platforms runs over HTTPS, making encryption the baseline expectation for shoppers. Shopify provides TLS certificates automatically for all Shopify-hosted storefronts.

Shop Pay adds another recognizable layer of trust at checkout. For returning Shop Pay users, their shipping and payment details are already stored securely, which reduces checkout friction.

Third-party trust badges (from security vendors or payment networks) can supplement these signals on checkout pages, particularly for stores in industries where customers are more security-conscious, like health products or high-value goods. 

Privacy policies, data transparency, and customer confidence

GDPR requires stores selling to EU and UK customers to provide clear information about what customer data is collected, why it’s collected, and how it’s stored. Shopify’s automated privacy policy templates cover the core requirements for Shopify-hosted stores, and the Customer Privacy API supports cookie consent banners that meet GDPR standards.

A clear, readable privacy policy can also build trust. Privacy transparency has a direct effect on whether customers stay. Usercentrics’ State of Digital Trust in 2025 found that 36% of consumers have stopped using a website due to privacy concerns. 

Shopify undergoes independent SOC 1 and SOC 2 security audits every six months. These Service Organization Control (SOC) audits verify that Shopify’s controls around customer data encryption, access management, incident response, and physical infrastructure meet the required standards, giving store owners documented, third-party confirmation that the platform they’re running on is secure.