CVE-2021-32805: URL Redirection to Untrusted Site ('Open Redirect') in Flask-AppBuilder

Published Sep 8, 2021
·
Updated

Impact If using Flask-AppBuilder OAuth, an attacker can share a carefully crafted URL with a trusted domain for an application built with Flask-AppBuilder, this URL can redirect a user to a malicious site. This is an open redirect vulnerability

Patches Install Flask-AppBuilder 3.2.2 or above

Workarounds Filter HTTP traffic containing ?next={next-site} where the next-site domain is different from the application you are protecting

Other sources

Flask-AppBuilder is an application development framework, built on top of Flask. In affected versions if using Flask-AppBuilder OAuth, an attacker can share a carefully crafted URL with a trusted domain for an application built with Flask-AppBuilder, this URL can redirect a user to a malicious site. This is an open redirect vulnerability. To resolve this issue upgrade to Flask-AppBuilder 3.2.2 or above. If upgrading is infeasible users may filter HTTP traffic containing ?next={next-site} where the next-site domain is different from the application you are protecting as a workaround.

MITRE

Affected Software

3 affected componentsFixes available
Flask-appbuilder Project Flask-appbuilder<3.3.2
dpgaspar Flask-AppBuilder<3.3.2
pip/Flask-AppBuilder<3.3.2
3.3.2

Event History

Sep 8, 2021
CVE Published
via MITRE·05:45 PM
Data Sourced
via MITRE·05:45 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·06:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
Advisory Published
via GitHub·09:11 PM

Frequently Asked Questions

1

What is CVE-2021-32805?

CVE-2021-32805 is a vulnerability in Flask-AppBuilder, an application development framework built on top of Flask.

2

What is the severity of CVE-2021-32805?

The severity of CVE-2021-32805 is high, with a severity value of 6.1.

3

How does CVE-2021-32805 affect Flask-AppBuilder?

In affected versions of Flask-AppBuilder, if using Flask-AppBuilder OAuth, an attacker can share a carefully crafted URL with a trusted domain for an application built with Flask-AppBuilder, redirecting users to a malicious site.

4

What is the affected software of CVE-2021-32805?

The affected software is Flask-AppBuilder version up to exclusive 3.3.2.

5

Is there a fix for CVE-2021-32805?

Yes, updating Flask-AppBuilder to a version beyond 3.3.2 will resolve the vulnerability.

Contact

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