Description
The Klarna for WooCommerce plugin for WordPress is vulnerable to authorization bypass in all versions up to, and including, 4.13.3 This is due to the plugin not properly verifying that a user is authorized to perform an action. This makes it possible for unauthenticated attackers to access any order's secret order_key and full billing and shipping PII — including first name, last name, email address, phone number, street address, postcode, city, region, and country — emitted inline as the klarna_payments_params JavaScript variable, enabling full store-wide order enumeration. Because WooCommerce order IDs are sequential integers and no order_key or authenticated session is required, every order in the store can be trivially enumerated with sequential GET requests to the order-pay endpoint.
References
https://www.wordfence.com/threat-intel/vulnerabilities/id/c3abb96e-6ee2-4992-a122-9f661da9a4d6?source=cve
https://plugins.trac.wordpress.org/changeset/3740915/klarna-payments-for-woocommerce/trunk/classes/class-kp-assets.php
https://plugins.trac.wordpress.org/browser/klarna-payments-for-woocommerce/tags/4.13.3/classes/class-kp-assets.php#L204
https://plugins.trac.wordpress.org/browser/klarna-payments-for-woocommerce/tags/4.13.3/classes/class-kp-assets.php#L198
https://plugins.trac.wordpress.org/browser/klarna-payments-for-woocommerce/tags/4.13.3/classes/class-kp-assets.php#L185
https://plugins.trac.wordpress.org/browser/klarna-payments-for-woocommerce/tags/4.13.3/classes/class-kp-assets.php#L159
https://github.com/krokedil/klarna-payments-for-woocommerce/compare/4.13.3...f5362605a9901b7f9264cfa3b22fd782a7a3097b
https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-102650