CVE-2021-29621 Explained : Impact and Mitigation

Flask-AppBuilder <= 3.2.3 is a development framework based on Flask that is impacted by a user enumeration vulnerability in database authentication. Upgrading to version 3.3.0 or higher is necessary to mitigate this issue.

Understanding CVE-2021-29621

This CVE identifies an observable response discrepancy in Flask-AppBuilder, potentially allowing unauthorized users to enumerate existing accounts.

What is CVE-2021-29621?

Flask-AppBuilder, up to version 3.2.3, is vulnerable to user enumeration in database authentication. This vulnerability enables non-authenticated users to identify existing accounts by timing the server's response during login attempts.

The Impact of CVE-2021-29621

The impact of this vulnerability is rated as MEDIUM with a CVSS v3.1 base score of 5.3. It poses a low risk to confidentiality but does not affect integrity or availability. The attack vector is through the network with no privileges required.

Technical Details of CVE-2021-29621

This section delves into the specifics of the vulnerability.

Vulnerability Description

The flaw in Flask-AppBuilder allows unauthorized users to enumerate accounts through response time analysis during login attempts.

Affected Systems and Versions

Flask-AppBuilder versions up to 3.2.3 are impacted by this vulnerability.

Exploitation Mechanism

Attackers can exploit this vulnerability by observing timing discrepancies in the server's responses during login authentication.

Mitigation and Prevention

To address CVE-2021-29621, specific steps need to be taken.

Immediate Steps to Take

Users should upgrade Flask-AppBuilder to version 3.3.0 or higher to mitigate the vulnerability effectively.

Long-Term Security Practices

Following secure coding practices and regularly updating software can help prevent such vulnerabilities in the future.

Patching and Updates

It is crucial to stay informed about security patches and promptly apply updates to maintain a secure development environment.