CVE-2026-43925: Fossbilling

Medium severity, CVSS 6.9. EPSS: 0.5% chance of exploitation in the next 30 days.

FOSSBilling is a free, open-source billing and client management system. Prior to version 0.8.0, an unauthenticated mass assignment vulnerability in the client self-registration endpoint allows any visitor to assign themselves to an arbitrary client group during sign-up. Because client groups can gate promo code eligibility, an attacker may apply group-restricted discount codes and receive unauthorized discounts. Version 0.8.0 contains a patch. As a workaround, administrators can either remove group restrictions from promo codes or disable client self-registration (Settings → Clients → Disable signup).

Affected products

• Fossbilling Fossbilling: before 0.8.0 (fixed in 0.8.0)

Published 2026-07-06. Last modified 2026-07-07.