CVE-2026-33430: Briefcase is a tool for converting a Python project into a standalone native application

Q: How do I fix CVE-2026-33430?

briefcase: upgrade to 0.3.26. Exact commands for each OS are on this page.

Q: Is CVE-2026-33430 being exploited?

CVE-2026-33430 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2026-33430 affect?

CVE-2026-33430 affects briefcase. Severity is high (CVSS 7.3). 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 proje

Routine

HIGH 7.3UPGRADE

CVE-2026-33430 is a high-severity flaw (CVSS 7.3) affecting briefcase. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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 installi

Why this priority

High severity

A fixed release or distro patch exists.

Risk facts

CVSS score	7.3 (High)
Attack vector	Local
Attack complexity	Low
Privileges needed	Low
User interaction	Required
EPSS exploit chance	0.1% (top 97%)
CISA exploited list	No
Weakness	CWE-732
Published	2026-03-26
Last modified	2026-06-17

Publisher (CNA): GitHub, Inc. · Vendor: beeware

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-03-26 17:16 UTCPublished CVE record published
2026-06-17 10:37 UTCUpdated Record last modified

beeware briefcase UPGRADE

Affected: >= 0.3.0 and < 0.3.26

Fixed in: 0.3.26

Safe to downgrade to: a release before 0.3.0

1. Check installed version

pip show briefcase

2. UPGRADE to 0.3.26

pip install --upgrade "briefcase>=0.3.26"

3. If no update is available yet, DOWNGRADE to a release before 0.3.0

pip index versions briefcase pip install "briefcase<0.3.0"

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-33430?

briefcase: upgrade to 0.3.26. Exact commands for each OS are on this page.

Is CVE-2026-33430 being exploited?

CVE-2026-33430 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-33430 affect?

CVE-2026-33430 affects briefcase. Severity is high (CVSS 7.3). 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 proje

How urgent is CVE-2026-33430?

Priority 26/100. High severity

Software pages

Python vulnerabilities · Windows vulnerabilities

References

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