CVE-2026-53648
MediumCVSS 5.1Exploitation Probability (EPSS)
Low risk18th percentile - higher than 18% of all known CVEs
Summary
In FOSSBilling prior to version 0.8.1, downloadable product files are stored using a deterministic filename-derived path (MD5 hash). Two different products or order files with the same original filename overwrite each other, causing customers or administrators to receive the wrong file.
Risk Assessment
The organization risks delivering unauthorized or malicious files to customers instead of ordered products, potentially leading to data integrity breaches, loss of trust, and legal consequences.
Recommendation
Immediately upgrade FOSSBilling to version 0.8.1 or later. As a temporary workaround, restrict the 'servicedownloadable.manage' permission to fully trusted administrators and ensure unique filenames before upload.
Other vulnerabilities in FOSSBilling
See all- CVE-2026-42341Critical
FOSSBilling versions 0.6.0 through 0.7.2 have an unauthenticated payment bypass vulnerability. An attacker can mark any unpaid invoice as paid and credit the client account by sending a single crafted HTTP request to the IPN callback endpoint.
- CVE-2026-33543Critical
FOSSBilling versions 0.7.2 and prior have a vulnerability in the guest API that allows the creation of new administrator accounts even when one already exists. A flaw in the admin existence check enables an attacker to bypass protections.
- CVE-2026-28496Critical
FOSSBilling prior to version 0.8.0 has a Server-Side Template Injection (SSTI) vulnerability in the template rendering system. Administrators can inject arbitrary Twig expressions, leading to information disclosure and remote code execution.
- CVE-2026-27604Critical
FOSSBilling versions 0.5.4 to 0.8.0 have an authorization bypass in API role handling, allowing unauthenticated access to privileged `/api/system/*` endpoints. Attackers can invoke admin API methods without valid credentials.
- CVE-2026-53647Medium
In FOSSBilling versions 0.5.3 through 0.7.2, the Guest `serviceapikey/get_info` API endpoint is accessible without authentication. Any caller with a valid API key can retrieve all custom configuration parameters (`custom_*` fields) stored in the key's database record.
- CVE-2026-53646High
In FOSSBilling versions 0.5.6 through 0.7.2, when a client requests a password reset multiple times, the system reuses the existing token instead of generating a new one, with the 15-minute validity anchored to the first request. An attacker who obtained the original reset link can still use it even after the victim requests a new reset, as the original token is never invalidated.
- CVE-2026-53645High
FOSSBilling prior to version 0.8.0 contains a vulnerability that allows a low-privileged staff account to escalate privileges via the admin API. A user with the `staff.create_and_edit_staff` permission can call `/api/admin/staff/permissions_update` for their own account and set any permissions, bypassing role-based access control.
- CVE-2026-53644High
FOSSBilling versions 0.5.3 through 0.7.2 allow authenticated clients to read and reset API key secrets for orders that are no longer active (e.g., suspended, canceled). The root cause is missing order-state validation in two client API endpoints, despite an `isActive()` helper existing in the `Serviceapikey` module and the frontend UI correctly gating access on active orders.
- CVE-2026-53643High
FOSSBilling versions prior to 0.8.0 allow low-privileged staff accounts to perform unauthorized actions via admin API endpoints. The root cause is a combination of the `can_always_access` module flag and insufficient permission checks or unsafe parameter handling on individual endpoints.
- CVE-2026-53642Medium
In FOSSBilling versions 0.5.6 through 0.7.2, when the 'Require Email Confirmation' setting is enabled, a logged-in client with an unverified email address can access all client-area pages, such as wallet balance and transaction history. The API-side enforcement works correctly, but the page-side enforcement is overly permissive, allowing any request starting with '/client'.
Original NVD description (English source)
FOSSBilling is a free, open-source billing and client management system. Prior to version 0.8.1, downloadable product files are stored using a deterministic filename-derived path. When an administrator uploads a file for a downloadable product, FOSSBilling stores the file as `md5(<original filename>)` under the uploads directory. Because the stored path depends only on the client-supplied filename, two different downloadable products, or product/order files, uploaded with the same original filename will resolve to the same stored file path. A later upload can overwrite an earlier upload, causing customers or administrators downloading the earlier product to receive the later file instead. Version 0.8.1 patches the issue. Some workarounds are available. Restrict the `servicedownloadable.manage` permission to fully trusted administrators only. As an operational mitigation, ensure downloadable product files use unique filenames before upload. This reduces accidental collisions but does not fully address the underlying issue.