Vulnerability Description
Briefcase is a tool for converting a Python project into a standalone native application. Starting in version 0.3.0 and prior to version 0.3.26, if a developer uses Briefcase to produce an Windows MSI installer for a project, and that project is installed for All Users (i.e., per-machine scope), the installation process creates an directory that inherits all the permissions of the parent directory. Depending on the location chosen by the installing user, this may allow a low privilege but authenticated user to replace or modify the binaries installed by the application. If an administrator then runs the altered binary, the binary will run with elevated privileges. The problem is caused by the template used to generate the WXS file for Windows projects. It was fixed in the templates used in Briefcase 0.3.26, 0.4.0, and 0.4.1. Re-running `briefcase create` on your Briefcase project will result in the updated templates being used. As a workaround, the patch can be added to any existing Briefcase .wxs file generated by Briefcase 0.3.24 or later.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Beeware | Briefcase | >= 0.3.0, < 0.3.26 |
Related Weaknesses (CWE)
References
- https://github.com/beeware/briefcase-windows-VisualStudio-template/pull/85Issue TrackingPatch
- https://github.com/beeware/briefcase-windows-app-template/pull/86Issue TrackingPatch
- https://github.com/beeware/briefcase/issues/2759Issue Tracking
- https://github.com/beeware/briefcase/security/advisories/GHSA-r3r2-35v9-v238MitigationPatchVendor Advisory
FAQ
What is CVE-2026-33430?
CVE-2026-33430 is a vulnerability with a CVSS score of 7.3 (HIGH). Briefcase is a tool for converting a Python project into a standalone native application. Starting in version 0.3.0 and prior to version 0.3.26, if a developer uses Briefcase to produce an Windows MSI...
How severe is CVE-2026-33430?
CVE-2026-33430 has been rated HIGH with a CVSS base score of 7.3/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-33430?
Check the references section above for vendor advisories and patch information. Affected products include: Beeware Briefcase.