How to fix missing content security policy on Adobe Commerce (Magento)

Steps for Adobe Commerce (Magento)

1. Adobe Commerce has native CSP support (introduced in Magento 2.3.5+).
2. In the Admin panel go to Stores → Configuration → Security → Content Security Policy.
3. Set 'CSP Mode' to 'Restrict Mode' (enforced) — start with 'Report Only Mode' to gather violations first.
4. Add your trusted domains for each directive (script-src, style-src, img-src, etc.) in the respective fields.
5. To add additional directives or fine-tune, edit app/etc/config.php or create a csp_whitelist.xml file inside your custom module's etc/ directory following the Magento CSP whitelist XML schema.
6. Deploy the changes and verify the header appears in browser DevTools.

What is missing content security policy?

A Content Security Policy (CSP) is an instruction you send to your visitors' web browsers, embedded in a special HTTP header, that tells the browser exactly which sources of scripts, images, styles, fonts, and other content it is allowed to load on your site. Think of it as a strict guest list at a nightclub door: anything not on the list gets turned away. Without a CSP header, the browser will happily load resources from anywhere — including malicious scripts injected by attackers. Your site currently sends no CSP header at all, which means that protection layer is completely absent.

Without a CSP, your store is significantly more vulnerable to Cross-Site Scripting (XSS) attacks — one of the most common ways attackers steal customer data, hijack sessions, or install payment-skimming code (like Magecart) directly in your shoppers' browsers. A successful XSS attack can expose customers' credit card numbers, passwords, and personal information, leading to chargebacks, fines under GDPR/CCPA, PCI-DSS violations, and severe reputational damage. Google also considers site security as a ranking signal, so a visibly compromised site can lose organic search rankings fast. Adding a CSP is recognized by OWASP as a critical defense-in-depth control against injection attacks (A03:2021).

See the complete Missing content security policy guide for every platform and the full background.