Improper Authentication in Flask-AppBuilder
Impact
Improper authentication on the REST API. Allows for a malicious actor with a carefully crafted request to successfully authenticate and gain access to existing protected REST API endpoints. Only affects non database authentication types, and new REST API endpoints.
Patches
Upgrade to Flask-AppBuilder 3.3.4
For more information
If you have any questions or comments about this advisory:
- Open an issue in https://github.com/dpgaspar/Flask-AppBuilder
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Python (PyPI) | flask-appbuilder | < 3.3.4 | 3.3.4 |
References
- https://github.com/dpgaspar/Flask-AppBuilder/security/advisories/GHSA-m3rf-7m4w-r66q
- https://github.com/dpgaspar/Flask-AppBuilder/commit/eba517aab121afa3f3f2edb011ec6bc4efd61fbc
- https://github.com/dpgaspar/Flask-AppBuilder/releases/tag/v3.3.4
- https://nvd.nist.gov/vuln/detail/CVE-2021-41265
- https://github.com/dpgaspar/Flask-AppBuilder
- https://github.com/pypa/advisory-database/tree/main/vulns/flask-appbuilder/PYSEC-2021-851.yaml
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N- Weakness (CWE)
CWE-287- Platform
- Python (PyPI)
- Package
flask-appbuilder- Disclosed
- 09.12.2021
- Updated
- 11.10.2026 13:19
Sources and licenses
OSV / GitHub Advisory Database - PYSEC-2021-851 - PyPA Advisory Database; CC BY 4.0
OSV / GitHub Advisory Database - GHSA-m3rf-7m4w-r66q - CC BY 4.0
Vulnerability history: flask-appbuilder
All published vulnerabilities of this package (Python (PyPI)), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 14
- First → latest
- 05.2021 09.2025
- Without a fix
- 0
- Exploited in attacks
- 0
Severity breakdown
- Critical 1
- High 2
- Medium 9
- Low 2
Disclosures per year
- 2021: 3
- 2022: 3
- 2023: 2
- 2024: 3
- 2025: 3
- 2026: 0
-
Improper Authentication in Flask-AppBuilder this entry
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