CVE-2021-29621: Apache Airflow

Medium severity, CVSS 5.3. EPSS: 3.4% chance of exploitation in the next 30 days.

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.

Affected products

• Apache Airflow: version 1.10.0 only
• Dpgaspar Flask-Appbuilder: up to and including 3.2.3

Published 2021-06-07. Last modified 2026-06-17.