CVE-2026-53640 FOSSBilling missing authorization checks on read-only admin API endpoints expose sensitive staff, client, and redirect data

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...

EUVD-2026-41965

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-2026-53640

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-2026-43927

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-2026-43928

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-2026-43918

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-2026-43921

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-2026-43928 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: 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...

EUVD-2026-41963

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-2026-43927 FOSSBilling has race condition in cart checkout that bypasses promo code usage limits

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-2026-43925

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...

EUVD-2026-41961

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-2026-43921 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 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-2026-43918

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...