What the vulnerability does
01Description
The Flow Payment plugin for WordPress (flow.cl) version 3.0.8 is vulnerable to reflected cross-site scripting on the WooCommerce checkout page. When the plugin handles an order cancellation, the error_message GET parameter is passed directly to wc_add_notice() in flowpayment-fl.php (lines 57-58) without input sanitization (for example sanitize_text_field()) or output escaping (for example esc_html()) before being rendered in the checkout notice HTML. An unauthenticated attacker can craft a URL containing a JavaScript payload in the error_message parameter (for example /checkout/?add-to-cart={product-id}&cancel_order=true&error_message={payload}); when a victim with an active WooCommerce checkout session follows the link, the payload executes in the victim's browser in the origin of the WordPress site.
Explanation of Vulnerability in Simple Terms
02Summary
Flow Payment versions 3.0.8 and earlier contain a cross-site scripting (XSS) vulnerability. An attacker can inject malicious scripts that execute in a victim's browser when they visit a crafted link or page. The vulnerability requires user interaction and has limited impact—it can read non-sensitive page content but cannot modify data or access the site.
What an attacker can do
03Attacker Capabilities
Inject malicious scripts that run in a victim's browser and read non-sensitive page content.
Potential impact on your site
04Site Impact
Users visiting malicious links could have their session data or non-sensitive information exposed; site data integrity is not at risk.
Conditions required to exploit
05Prerequisites
Victim must click a malicious link or visit an attacker-controlled page while logged into or viewing the vulnerable site.
Key dates
06Disclosure timeline
July 18, 2026
CVE published
July 20, 2026
Record updated
