CVE-2026-53640

FOSSBilling is a free, open-source billing and client management system. Prior to version 0.8.0, low-privileged staff accounts may read sensitive data via admin API endpoints that lack permission checks. While sibling write endpoints correctly enforce fine-grained permissions, the corresponding...

CVE-2026-43928

FOSSBilling is a free, open-source billing and client management system. Prior to version 0.8.0, the PayPalEmail payment adapter accepts PayPal IPN callbacks and credits the IPN-supplied amount mcgross to the client's balance without validating it against the invoice total. Combined with a $0.05...

CVE-2026-43927

FOSSBilling is a free, open-source billing and client management system. Prior to version 0.8.0, a race condition in the cart checkout flow allows an authenticated client to apply a promo code beyond its configured maximum uses. By sending concurrent checkout requests before any single request...

CVE-2026-43921

FOSSBilling is a free, open-source billing and client management system. Versions 0.6.10 through 0.7.2 have a PHP code injection vulnerability in FOSSBilling's Config::prettyPrintArrayToPHP method. When configuration values are updated, string values are written into config.php without escaping...

CVE-2026-43918

FOSSBilling is a free, open-source billing and client management system. Prior to version 0.8.0, when a client or staff/admin account is suspended or marked inactive, existing authenticated sessions are not invalidated. The session identity loaders in src/di.php loggedinclient and loggedinadmin...

CVE-2026-43928 FOSSBilling: Payment amount not validated in PayPalEmail adapter allows invoice underpayment

FOSSBilling is a free, open-source billing and client management system. Prior to version 0.8.0, the PayPalEmail payment adapter accepts PayPal IPN callbacks and credits the IPN-supplied amount mcgross to the client's balance without validating it against the invoice total. Combined with a $0.05...

CVE-2026-43928

FOSSBilling PayPalEmail integration before 0.8.0 credits mc_gross from IPN without validating against the invoice total, combined with a $0.05 epsilon in the credit logic, enabling underpayment of up to $0.04 while marking invoices as paid. Version 0.8.0 patches the issue. No public workaround ex...

CVE-2026-43925

FOSSBilling (open-source billing/client management) contains an unauthenticated mass assignment vulnerability in the client self-registration endpoint, prior to version 0.8.0. An attacker can assign themselves to an arbitrary client group during sign-up, potentially bypassing group-restricted pro...

CVE-2026-43925 FOSSBilling: Mass assignment of group_id in guest client registration allows unauthorized promo code use

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...

CVE-2026-43921 FOSSBilling vulnerable to arbitrary PHP code injection via unescaped config serialization

FOSSBilling is a free, open-source billing and client management system. Versions 0.6.10 through 0.7.2 have a PHP code injection vulnerability in FOSSBilling's Config::prettyPrintArrayToPHP method. When configuration values are updated, string values are written into config.php without escaping...

CVE-2026-43921

FOSSBilling is a free, open-source billing and client management system. Versions 0.6.10 through 0.7.2 have a PHP code injection vulnerability in FOSSBilling's Config::prettyPrintArrayToPHP method. When configuration values are updated, string values are written into config.php without escaping...

CVE-2026-43921

FOSSBilling is affected by a PHP code injection in versions 0.6.10–0.7.2 via Config::prettyPrintArrayToPHP(), where updated configuration values are written to config.php without escaping single quotes. Because config.php is loaded with a bare include on each HTTP request, an admin with privilege...

CVE-2026-43918

FOSSBilling before 0.8.0 does not invalidate existing sessions for suspended or inactive accounts. The session identity loaders (loggedin_client and loggedin_admin) only reject sessions if the backing account record no longer exists; they do not check that the account’s status remains active. Thi...

CVE-2026-43918 Suspended or inactive FOSSBilling accounts can retain or regain access through existing sessions, API tokens, and password reset flows

FOSSBilling is a free, open-source billing and client management system. Prior to version 0.8.0, when a client or staff/admin account is suspended or marked inactive, existing authenticated sessions are not invalidated. The session identity loaders in src/di.php loggedinclient and loggedinadmin...

CVE-2026-33734

FOSSBilling is a free, open-source billing and client management system. Versions 0.6.0 through 0.7.2 have a SQL injection vulnerability in the Massmailer module filter functionality. An authenticated administrator can supply crafted filter values when updating a mass email message, causing...

CVE-2026-42331 FOSSBilling missing authorization in guest Invoice API endpoints

FOSSBilling is a free, open-source billing and client management system. Prior to version 0.8.0, the Guest API invoice/update endpoint is missing an authorization check present in other invoice-related endpoints, allowing an unauthenticated user with knowledge of an invoice hash to modify the...

CVE-2026-42331

FOSSBilling is a free, open-source billing and client management system. Prior to version 0.8.0, the Guest API invoice/update endpoint is missing an authorization check present in other invoice-related endpoints, allowing an unauthenticated user with knowledge of an invoice hash to modify the...

CVE-2026-42331

FOSSBilling before version 0.8.0 has an authorization gap in the Guest API invoice/update endpoint. An unauthenticated attacker who knows an invoice hash can modify the payment gateway associated with an unpaid invoice, potentially changing gateway_id to any gateway configured in the system. The ...

CVE-2026-33734 FOSSBilling has improper SQL neutralization in `Massmailer` recipient filters

FOSSBilling is a free, open-source billing and client management system. Versions 0.6.0 through 0.7.2 have a SQL injection vulnerability in the Massmailer module filter functionality. An authenticated administrator can supply crafted filter values when updating a mass email message, causing...

CVE-2026-33734 FOSSBilling has improper SQL neutralization in `Massmailer` recipient filters

FOSSBilling is a free, open-source billing and client management system. Versions 0.6.0 through 0.7.2 have a SQL injection vulnerability in the Massmailer module filter functionality. An authenticated administrator can supply crafted filter values when updating a mass email message, causing...