{"cve":"CVE-2021-41265","nvd":{"published":"2021-12-09T17:15:07.963","modified":"2026-06-17T04:08:12.030","status":"Modified","description":"Flask-AppBuilder is a development framework built on top of Flask. Verions prior to 3.3.4 contain an improper authentication vulnerability in the REST API. The issue allows for a malicious actor with a carefully crafted request to successfully authenticate and gain access to existing protected REST API endpoints. This only affects non database authentication types and new REST API endpoints. Users should upgrade to Flask-AppBuilder 3.3.4 to receive a patch.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":8.8},"cwes":["CWE-287"],"references":["https://github.com/dpgaspar/Flask-AppBuilder/commit/eba517aab121afa3f3f2edb011ec6bc4efd61fbc","https://github.com/dpgaspar/Flask-AppBuilder/releases/tag/v3.3.4","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"],"products":["dpgaspar:flask-appbuilder"],"source":"nvd","synced_at":"2026-10-19T21:25:41.256909649+00:00"},"epss":{"cve":"CVE-2021-41265","score":0.01317,"percentile":0.70792,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-m3rf-7m4w-r66q","url":"https://osv.dev/vulnerability/GHSA-m3rf-7m4w-r66q","summary":"Improper Authentication in Flask-AppBuilder","modified":"2026-07-08T06:29:22.945111844Z","packages":[{"ecosystem":"PyPI","name":"flask-appbuilder","purl":"pkg:pypi/flask-appbuilder","ranges":["<3.3.4"],"fixed":["3.3.4"]}]},{"id":"PYSEC-2021-851","url":"https://osv.dev/vulnerability/PYSEC-2021-851","summary":"","modified":"2023-11-08T04:06:57.790783Z","packages":[{"ecosystem":"PyPI","name":"flask-appbuilder","purl":"pkg:pypi/flask-appbuilder","ranges":["<3.3.4"],"fixed":["3.3.4"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}