{"cve":"CVE-2021-29621","nvd":{"published":"2021-06-07T19:15:07.600","modified":"2026-06-17T03:48:02.597","status":"Modified","description":"Flask-AppBuilder is a development framework, built on top of Flask. User enumeration in database authentication in Flask-AppBuilder <= 3.2.3. Allows for a non authenticated user to enumerate existing accounts by timing the response time from the server when you are logging in. Upgrade to version 3.3.0 or higher to resolve.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","score":5.3},"cwes":["CWE-203"],"references":["https://github.com/dpgaspar/Flask-AppBuilder/commit/780bd0e8fbf2d36ada52edb769477e0a4edae580","https://github.com/dpgaspar/Flask-AppBuilder/security/advisories/GHSA-434h-p4gx-jm89","https://lists.apache.org/thread.html/r466759f377651f0a690475d5a52564d0e786e82c08d5a5730a4f8352%40%3Cannounce.apache.org%3E","https://lists.apache.org/thread.html/r5b754118ba4e996adf03863705d34168bffec202da5c6bdc9bf3add5%40%3Cannounce.apache.org%3E","https://lists.apache.org/thread.html/r91067f953906d93aaa1c69fe2b5472754019cc6bd4f1ba81349d62a0%40%3Ccommits.airflow.apache.org%3E"],"products":["apache:airflow","dpgaspar:flask-appbuilder"],"source":"nvd","synced_at":"2026-10-19T21:20:07.141963181+00:00"},"epss":{"cve":"CVE-2021-29621","score":0.03404,"percentile":0.8886,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-434h-p4gx-jm89","url":"https://osv.dev/vulnerability/GHSA-434h-p4gx-jm89","summary":"Observable Response Discrepancy in Flask-AppBuilder","modified":"2026-07-08T06:27:56.529823809Z","packages":[{"ecosystem":"PyPI","name":"flask-appbuilder","purl":"pkg:pypi/flask-appbuilder","ranges":["<3.3.0"],"fixed":["3.3.0"]}]},{"id":"PYSEC-2021-90","url":"https://osv.dev/vulnerability/PYSEC-2021-90","summary":"","modified":"2023-12-06T01:01:09.861844Z","packages":[{"ecosystem":"PyPI","name":"flask-appbuilder","purl":"pkg:pypi/flask-appbuilder","ranges":["<3.3.0"],"fixed":["3.3.0"]}]}],"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."]}