CVE-2026-33734

Summary: CVE-2026-33734 affects FOSSBilling. Versions 0.6.0–0.7.2 contain an SQL injection in the Massmailer module’s recipient filter functionality. An authenticated administrator can supply crafted filter values when updating a mass email message, causing untrusted input to be interpolated dire...

CVE-2026-42341

FOSSBilling versions 0.6.0–0.7.2 contain an unauthenticated payment bypass in the IPN callback endpoint. When the Custom payment adapter is enabled, an attacker can mark any unpaid invoice as paid and credit the client account without a real payment by sending a crafted HTTP request. Version 0.8....

CVE-2026-42341 FOSSBilling has an unauthenticated payment bypass via IPN callback forgery

FOSSBilling is a free, open-source billing and client management system. Versions 0.6.0 through 0.7.2 have an unauthenticated payment bypass vulnerability in FOSSBilling's IPN callback endpoint. When the Custom payment adapter is enabled, an attacker can mark any unpaid invoice as paid and credit...

PT-2026-56034

Name of the Vulnerable Software and Affected Versions FOSSBilling versions 0.6.0 through 0.7.2 Description A stored cross-site scripting XSS issue exists in the client-facing email history views. This occurs because email HTML content, specifically the content html variable, is rendered into a...

PT-2026-56035

Name of the Vulnerable Software and Affected Versions FOSSBilling versions 0.5.6 through 0.7.2 Description When the Require Email Confirmation setting is enabled, a logged-in client with an unverified email address, indicated by the variable email approved = 0, can bypass page-side enforcement...

PT-2026-56033

Name of the Vulnerable Software and Affected Versions FOSSBilling versions prior to 0.8.0 Description Low-privileged staff accounts can read sensitive data through admin API endpoints that lack proper permission checks. Although write endpoints enforce fine-grained permissions, the corresponding...

PT-2026-56038

Name of the Vulnerable Software and Affected Versions FOSSBilling versions prior to 0.8.0 Description A low-privileged staff account can grant arbitrary module permissions to itself, leading to persistent privilege escalation. A user possessing the staff.create and edit staff permission can call...

PT-2026-56010

Name of the Vulnerable Software and Affected Versions FOSSBilling versions 0.6.0 through 0.7.2 Description An unauthenticated payment bypass exists in the IPN callback endpoint /ipn.php. When the Custom payment adapter is enabled, an attacker can mark any unpaid invoice as paid and credit the...

PT-2026-56031

Name of the Vulnerable Software and Affected Versions FOSSBilling versions prior to 0.8.0 Description A race condition in the cart checkout flow allows an authenticated client to apply a promo code more times than its configured maximum limit. By sending concurrent checkout requests before the...

PT-2026-56037

Name of the Vulnerable Software and Affected Versions FOSSBilling versions 0.5.3 through 0.7.2 Description Authenticated clients can read and reset API key service secrets for orders that are not in an active state, such as suspended or canceled. This occurs due to missing order-state validation ...

PT-2026-56036

Name of the Vulnerable Software and Affected Versions FOSSBilling versions prior to 0.8.0 Description Low-privileged staff accounts can perform unauthorized actions through admin API endpoints. This issue stems from the can always access module flag, which grants all staff access to specific...

PT-2026-56028

Name of the Vulnerable Software and Affected Versions FOSSBilling versions 0.6.10 through 0.7.2 Description An issue exists in the Config::prettyPrintArrayToPHP method where string values are written into the config.php file without escaping single quotes during configuration updates. Since...

FOSSBilling - Server-Side Template Injection

A Server-Side Template Injection SSTI vulnerability exists in FOSSBilling's template rendering system. Administrators with access to features that render Twig templates email templates, mass mail campaigns, custom payment adapters, and the stringrender API endpoint can inject arbitrary Twig...

CVE-2026-43920

FOSSBilling is a free, open-source billing and client management system. In versions 0.5.4 through 0.7.2, the /run-patcher maintenance endpoint in FOSSBilling was accessible without authentication, which allowed unauthenticated remote users to trigger update patch routines that modify configurati...

CVE-2026-43920

CVE-2026-43920 affects FOSSBilling versions 0.5.4–0.7.2 where the unauthenticated /run-patcher endpoint allowed privileged maintenance operations (config migrations, DB schema changes including ALTER/DROP/UPDATE, filesystem deletions/renames, and cache clearing) to be executed without admin auth,...

CVE-2026-43920 FOSSBilling: Unauthenticated update patcher endpoint allows remote maintenance execution

FOSSBilling is a free, open-source billing and client management system. In versions 0.5.4 through 0.7.2, the /run-patcher maintenance endpoint in FOSSBilling was accessible without authentication, which allowed unauthenticated remote users to trigger update patch routines that modify configurati...

VulnCheck KEV: CVE-2026-28496

FOSSBilling is a free, open-source billing and client management system. Versions prior to 0.8.0 have a Server-Side Template Injection SSTI vulnerability in the template rendering system. Administrators with access to features that render Twig templates email templates, mass mail campaigns, custo...

CVE-2026-33543

FOSSBilling is a free, open-source billing and client management system. Versions 0.7.2 and prior expose a guest API endpoint, /api/guest/staff/create, intended for initial administrator bootstrap. Due to a flawed admin-existence check, the endpoint remains usable after an administrator already...

CVE-2026-33543

FOSSBilling versions 0.7.2 and earlier expose a guest API endpoint /api/guest/staff/create intended for initial admin bootstrap. A flawed admin-existence check (is_countable() used on a Model_Admin object or null) makes the guard always evaluate true, allowing unauthenticated creation of an admin...

CVE-2026-33543 FOSSBilling: Authentication bypass allows unauthenticated administrator creation

FOSSBilling is a free, open-source billing and client management system. Versions 0.7.2 and prior expose a guest API endpoint, /api/guest/staff/create, intended for initial administrator bootstrap. Due to a flawed admin-existence check, the endpoint remains usable after an administrator already...