CVE-2026-27964

Description

FacturaScripts is an open source accounting and invoicing software. Versions 2025.7 and prior contain a Reflected Cross-Site Scripting (XSS) vulnerability through the fsNick cookie parameter. The application reflects the cookie-s value directly into the HTML without sanitization. The fsNick cookie is rendered into the DOM without encoding. While the server does reject the modified session and forces a logout, the HTML containing the payload reaches the browser first. This lets the script execute immediately upon load, effectively beating the redirect. This issue has been fixed in version 2025.8.