CVE-2026-53648 FOSSBilling: Downloadable product files can be overwritten through filename collisions
Attackers can overwrite downloadable product files by uploading files with identical names, causing customers to receive incorrect content.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-53648?
CVE-2026-53648 is a medium-severity vulnerability in FOSSBilling, published on 6 Jul 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Official description
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.
Which versions are affected by CVE-2026-53648?
How do I fix CVE-2026-53648?
No fix has been published for CVE-2026-53648 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-53648 being exploited?
There is no known exploitation of CVE-2026-53648 in the wild and no public exploit code.
Sources
Also known as GHSA-x7p2-xhvc-cfp9.