CVE-2021-29621: Observable Response Discrepancy in Flask-AppBuilder

Published May 27, 2021
·
Updated

Impact 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.

Patches Upgrade to 3.3.0

For more information If you have any questions or comments about this advisory: Open an issue in Flask-AppBuilder

Other sources

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.

MITRE

Affected Software

4 affected componentsFixes available
Flask-appbuilder Project Flask-appbuilder<=3.2.3
Apache Airflow=1.10.0
dpgaspar Flask-AppBuilder<=3.2.3
pip/Flask-AppBuilder<3.3.0
3.3.0

Event History

May 27, 2021
Advisory Published
via GitHub·06:38 PM
Jun 7, 2021
CVE Published
via MITRE·07:00 PM
Data Sourced
via MITRE·07:00 PM
DescriptionSeverityWeakness

Frequently Asked Questions

1

What is CVE-2021-29621?

CVE-2021-29621 is a vulnerability in Flask-AppBuilder <= 3.2.3 that allows a non-authenticated user to enumerate existing accounts by timing the response time from the server during login.

2

What is the severity of CVE-2021-29621?

The severity of CVE-2021-29621 is medium with a CVSS score of 5.3.

3

How does CVE-2021-29621 affect Flask-AppBuilder?

CVE-2021-29621 affects Flask-AppBuilder versions up to and including 3.2.3.

4

How can I fix CVE-2021-29621?

To fix CVE-2021-29621, upgrade Flask-AppBuilder to version 3.3 or higher.

5

Is Apache Airflow affected by CVE-2021-29621?

Yes, Apache Airflow version 1.10.0 is also affected by CVE-2021-29621.

Contact

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